need RAM recommendation - please help

"Paul" wrote in message
...
glee wrote:
"Paul" wrote in message
...
Adam wrote:
Need RAM recommendation for the following motherboard ...

- ASUS M5A99X Evo - AM3+ - 990X - SATA 6Gbps and USB 3.0 - ATX DDR3
2133 Motherboards

I am thinking about the following ...

- Crucial Ballistix 240-Pin DDR3

but need help with the specific model and amount (at least 8 GB due to
VirtualBox/VM usage).



Check the customer reviews on Newegg, for each product you are
interested in.

Some RAM has a high enough failure rate, you should stay away
from it.

The customer reviews, tells you what to avoid.

Well I wouldn't go solely by some customer reviews. RAM by all the major
suppliers (Crucial, Corsair, etc) is all good. Better to use RAM from
the approved list suggested by the board maker Asus.

This is categorically not true.

Some major manufacturers, have had *major* problems with reliability.
To the point they even switched chip supplier, when making the DIMMs
to try to stop it.

And this is why we read customer reviews, to easily gather (data mine)
the knowledge that is available.

If there is an obvious problem, and a lot of unhappy customers, the
customer reviews form a gross filter or "early warning system".

At one time, I would have sworn by Crucial Ballistix. Now, not so much.
They've had their problems over the years. Which is why you check
the customer reviews for "trending". Crucial had so much problems at
one point, they stopped shipping Micron chips on the DIMMs, and
started shipping Samsung. Just to give you some idea.

Some manufacturers, are "rebranders" and don't actually make the
RAM themselves. They don't actually have their own factory, churning
out DIMMs. But what they do have, is a good contracting system, having
the DIMMs made by third parties, tested, and then placing their own
sticker on the RAM. If the contractor violates their trust relationship,
they'll get turfed. Now, knowing that, imagine what the test results
might mean.

Sometimes, a SKU on Newegg, goes from "good" to "bad", on a lot basis.
Some RAM manufacturers have changed chip source (when the "good" chips
ran out), and if you're careful, you can spot the point in time that
the modules became not worth buying. This tends to happen for DIMMs
which extend past the official JEDEC range, and are "binned" or
"made by binning" type products with elevated operating voltages.
So if you were shopping for DDR3-2400, you might look for that
in the customer reviews.

We can't carry this "tea leaf" exercise too far. The idea is to
spot trends or intelligence *if available*. For example, there
was an issue at one time, with Micron D series silicon die, and
a certain family of processor. To the point it might even have
been mentioned on Anandtech. If you want, you can start sweeping the
net (Anandtech forums, Xtremesystems.org forums) for that kind of
knowledge. Using Newegg customer reviews, is an effort on my part,
to make this data mining exercise less onerous. But if you
*really* want to know a lot about RAM and RAM compatibility,
then you'd spend the extra couple hours finding out that way.
There are enthusiasts out there, who own twenty or thirty sets
of RAM, and test them all. And when they spot a trend, or notice
a problem with a new motherboard family, they can provide
interesting input.

This entry is a joke, but this is just to make a point.

http://www.newegg.com/Product/Produc...82E16813131754

"3/16/2012 4:02:48 PM Awesome board!

My ram wasn't on the list of compatible ram and it works fine."

At one level, you select RAM based on specs. Does a motherboard
family support all the RAM on the market ? DDR3 comes in "regular"
or "reduced voltage" RAM. At one time, Intel supported both and
AMD supported one of those. So one of your checks, would be
to see whether the broadest range of RAM is supported.

From the user manual for the motherboard:

"DRAM Voltage[Auto]

Allows you to set the DRAM voltage. The values range 1.20V to 2.20V"

So that tells me the board (depending on CPU type), can support
DDR3L. DDR3 nominal would be 1.5V, but there was some RAM
where the voltage spec is centered at 1.35V. So it looks like
that board is intended to cover both types. (The CPU actually
determines whether the support is there, but tracking this
down now on the AMD site, would be next to impossible.)

You do the best you can, to data mine before buying. It could
still happen, that you get a dud, or mismatch between your
board and the RAM purchase. The purpose of JEDEC standards,
is to try to make this process as painless as possible (broadest
compatibility), which is why you don't absolutely need to use
the Asus memory compatibility chart. But it makes some people
feel better. When I clicked the download link for M5A99X Evo
memory chart (from support.asus.com), this is the URL of the
download. It would appear they just copied the test results,
from another motherboard.

http://dlcdnet.asus.com/pub/ASUS/mb/...Memory_QVL.zip

To give another example of a "detected trend", when 2GB
modules first came out, the BIOS simply wasn't set up
on any board to properly handle them. The 1GB modules
might work fine for you, while the 2GB, you could try
all the tuning parameters on the board, and not get
the RAM stable. I have a motherboard here, with that
problem (that machine still has only 1GB modules in it).
As BIOS updates were handed out, this problem
gradually disappeared. And that observation, at the time,
would have influenced a RAM purchase (i.e. you would buy
4x1GB instead of 2x2GB, until they fixed that). If you
*didn't* read the enthusiast tea leaves at the time, you
would have missed that, and ended up with lots of
crashing misery. The Newegg's of the world, didn't stop
selling 2GB modules, while the problem existed. It
was eventually resolved, but in fact, not on my
motherboard :-( The 2GB modules are now in my
current machine, where they work fine.

Paul


Having 2nd thoughts about the motherboard. How do the following compare ...


ASUS Sabertooth 990FX AM3+ AMD 990FX SATA 6Gb/s USB 3.0 ATX AMD Motherboard
http://www.newegg.com/Product/Produc...82E16813131736

ASUS Crosshair V Formula AM3+ AMD 990FX SATA 6Gb/s USB 3.0 ATX AMD Gaming
Motherboard
http://www.newegg.com/Product/Produc...82E16813131735

ASUS M5A99X EVO AM3+ AMD 990X SATA 6Gb/s USB 3.0 ATX AMD Motherboard
http://www.newegg.com/Product/Produc...82E16813131754

Adam wrote:

Having 2nd thoughts about the motherboard. How do the following compare ...


ASUS Sabertooth 990FX AM3+ AMD 990FX SATA 6Gb/s USB 3.0 ATX AMD Motherboard
http://www.newegg.com/Product/Produc...82E16813131736

ASUS Crosshair V Formula AM3+ AMD 990FX SATA 6Gb/s USB 3.0 ATX AMD Gaming
Motherboard
http://www.newegg.com/Product/Produc...82E16813131735

ASUS M5A99X EVO AM3+ AMD 990X SATA 6Gb/s USB 3.0 ATX AMD Motherboard
http://www.newegg.com/Product/Produc...82E16813131754

I don't know what your objectives are for the build.

The chipsets differ in the PCI Express configuration.

http://en.wikipedia.org/wiki/AMD_900_chipset_series

"990FX

* PCI Express 2.0 (2x16 or 4x8 configurations)
* Support for up to 4 graphics cards
* 19.6 Watt TDP
* Southbridge: SB950

990X

* PCI Express 2.0 (1x16 or 2x8 configurations)
* Support for up to 2 graphics cards
* 14 Watt TDP
* Southbridge: SB950"

Some of the peripheral chips might be a deciding factor
(like if the external USB3 chips selected weren't the best).

But it's possible they might be equal in terms of running
a given processor at stock speeds.

But you'll have to fill me in on what your expectations are.

If you needed lots of PCI Express bandwidth, then the 990FX
is probably a good way to get it. You pay for it, with
a little bit extra Northbridge power usage.

The motherboard reputations aren't markedly different.
I think the most expensive board got a few more low
ratings, because when an expensive board fails expectations,
people usually judge it harshly. When I bought a $65 motherboard,
nobody really hated that one, because, well, it was only
$65, and what do you expect for $65. And that board
still works :-)

Paul

"Paul" wrote in message
...
Adam wrote:

Having 2nd thoughts about the motherboard. How do the following compare
...


ASUS Sabertooth 990FX AM3+ AMD 990FX SATA 6Gb/s USB 3.0 ATX AMD
Motherboard
http://www.newegg.com/Product/Produc...82E16813131736

ASUS Crosshair V Formula AM3+ AMD 990FX SATA 6Gb/s USB 3.0 ATX AMD Gaming
Motherboard
http://www.newegg.com/Product/Produc...82E16813131735

ASUS M5A99X EVO AM3+ AMD 990X SATA 6Gb/s USB 3.0 ATX AMD Motherboard
http://www.newegg.com/Product/Produc...82E16813131754


I don't know what your objectives are for the build.

The chipsets differ in the PCI Express configuration.

http://en.wikipedia.org/wiki/AMD_900_chipset_series

"990FX

* PCI Express 2.0 (2x16 or 4x8 configurations)
* Support for up to 4 graphics cards
* 19.6 Watt TDP
* Southbridge: SB950

990X

* PCI Express 2.0 (1x16 or 2x8 configurations)
* Support for up to 2 graphics cards
* 14 Watt TDP
* Southbridge: SB950"

Some of the peripheral chips might be a deciding factor
(like if the external USB3 chips selected weren't the best).

But it's possible they might be equal in terms of running
a given processor at stock speeds.

But you'll have to fill me in on what your expectations are.

If you needed lots of PCI Express bandwidth, then the 990FX
is probably a good way to get it. You pay for it, with
a little bit extra Northbridge power usage.

The motherboard reputations aren't markedly different.
I think the most expensive board got a few more low
ratings, because when an expensive board fails expectations,
people usually judge it harshly. When I bought a $65 motherboard,
nobody really hated that one, because, well, it was only
$65, and what do you expect for $65. And that board
still works :-)

Paul


Thanks (Guru Paul), so far, here is the components list ...

- ASUS M5A99X Evo - AM3+ - 990X - ATX DDR3 2133 Motherboards [under
consideration]
- G.SKILL Ripjaws X Series 16GB (4 x 4GB) 240-Pin DDR3 1600 (PC3 12800)
[under consideration]
- AMD Phenom II X4 [under consideration; will run processor at stock
speeds]
- Sapphire 100315L Radeon HD 6850 Video Card [already own; will be single
video card system]
- OCZ ModXStream Pro 600W Modular High Performance Power Supply [already
own]
- Antec Three Hundred ATX Mid Tower Gaming Computer Case [already own]

Objective is getting the best bang for the buck.

Adam wrote:
"Paul" wrote in message
...
Adam wrote:

Having 2nd thoughts about the motherboard. How do the following compare
...


ASUS Sabertooth 990FX AM3+ AMD 990FX SATA 6Gb/s USB 3.0 ATX AMD
Motherboard
http://www.newegg.com/Product/Produc...82E16813131736

ASUS Crosshair V Formula AM3+ AMD 990FX SATA 6Gb/s USB 3.0 ATX AMD Gaming
Motherboard
http://www.newegg.com/Product/Produc...82E16813131735

ASUS M5A99X EVO AM3+ AMD 990X SATA 6Gb/s USB 3.0 ATX AMD Motherboard
http://www.newegg.com/Product/Produc...82E16813131754

I don't know what your objectives are for the build.

The chipsets differ in the PCI Express configuration.

http://en.wikipedia.org/wiki/AMD_900_chipset_series

"990FX

* PCI Express 2.0 (2x16 or 4x8 configurations)
* Support for up to 4 graphics cards
* 19.6 Watt TDP
* Southbridge: SB950

990X

* PCI Express 2.0 (1x16 or 2x8 configurations)
* Support for up to 2 graphics cards
* 14 Watt TDP
* Southbridge: SB950"

Some of the peripheral chips might be a deciding factor
(like if the external USB3 chips selected weren't the best).

But it's possible they might be equal in terms of running
a given processor at stock speeds.

But you'll have to fill me in on what your expectations are.

If you needed lots of PCI Express bandwidth, then the 990FX
is probably a good way to get it. You pay for it, with
a little bit extra Northbridge power usage.

The motherboard reputations aren't markedly different.
I think the most expensive board got a few more low
ratings, because when an expensive board fails expectations,
people usually judge it harshly. When I bought a $65 motherboard,
nobody really hated that one, because, well, it was only
$65, and what do you expect for $65. And that board
still works :-)

Paul


Thanks (Guru Paul), so far, here is the components list ...

- ASUS M5A99X Evo - AM3+ - 990X - ATX DDR3 2133 Motherboards [under
consideration]
- G.SKILL Ripjaws X Series 16GB (4 x 4GB) 240-Pin DDR3 1600 (PC3 12800)
[under consideration]
- AMD Phenom II X4 [under consideration; will run processor at stock
speeds]
- Sapphire 100315L Radeon HD 6850 Video Card [already own; will be single
video card system]
- OCZ ModXStream Pro 600W Modular High Performance Power Supply [already
own]
- Antec Three Hundred ATX Mid Tower Gaming Computer Case [already own]

Objective is getting the best bang for the buck.



The only USB3 I know of, with a few problems, is Etron brand.

http://forums.tweaktown.com/asrock/4...0-problem.html

The M5A99X uses an Asmedia USB3 chip (a company which as far
as I know, is a subsidiary of Asus).

M5A99X EVO:

990X (1x16 or 2x8 video config)
SB950 (6 SATA III, No USB3)
(2) JMB362 (2 SATA II each)
RealTek 8111E (Ethernet NIC)
RealTek ALC892 (As long as you get at least stereo sound, you win...)
(2) AsMedia USB3 (four ports total, two ports full bandwidth)
VIA 6308P Firewire (Best were TI brand, or Lucent/Agere/LSI)

Of your PCI Express slots, install the video card in the top
slot, leave the second video card slot blank (to preserve the x16
interface rate), then you can use the x4 black slot for things
like a RAID card perhaps.

So the only shortcoming, is whether you consider the
video card slot running at x8 to be a problem or not.
x8 at PCI Express Rev2.0 rates, is 4GB/sec (8 lanes
times 500MB/sec transfer rate).

Check the reviews, see if the board has problems at higher
memory clock speeds, and perhaps you have a winner. That
board is certainly cheaper than the others. And the chipset
will run cooler.

With regard to the RAM, and how I'd run it, I'd buy the 4x4GB
kit (because DDR3 is cheap, but the price will rise as one
of the memory companies just got bought out). I'd operate
the motherboard with just two sticks (8GB). Then keep the
other two sticks as spares. Leaving two slots blank, improves
cooling around the memory slots. If you have a problem with
the 8GB, you just swap in the other pair. No downtime.

I bought a set of 8 DIMMs once, and three have failed.
Leaving me with five good ones :-)

The last RAM I bought, with zero failures, was in the
FPM/EDO era. Where it used to cost $600 to fill the computer
with RAM. RAM just doesn't hold up any more.

Paul

"Paul" wrote in message
...
Adam wrote:
"Paul" wrote in message
...
Adam wrote:

Having 2nd thoughts about the motherboard. How do the following
compare ...


ASUS Sabertooth 990FX AM3+ AMD 990FX SATA 6Gb/s USB 3.0 ATX AMD
Motherboard
http://www.newegg.com/Product/Produc...82E16813131736

ASUS Crosshair V Formula AM3+ AMD 990FX SATA 6Gb/s USB 3.0 ATX AMD
Gaming Motherboard
http://www.newegg.com/Product/Produc...82E16813131735

ASUS M5A99X EVO AM3+ AMD 990X SATA 6Gb/s USB 3.0 ATX AMD Motherboard
http://www.newegg.com/Product/Produc...82E16813131754

I don't know what your objectives are for the build.

The chipsets differ in the PCI Express configuration.

http://en.wikipedia.org/wiki/AMD_900_chipset_series

"990FX

* PCI Express 2.0 (2x16 or 4x8 configurations)
* Support for up to 4 graphics cards
* 19.6 Watt TDP
* Southbridge: SB950

990X

* PCI Express 2.0 (1x16 or 2x8 configurations)
* Support for up to 2 graphics cards
* 14 Watt TDP
* Southbridge: SB950"

Some of the peripheral chips might be a deciding factor
(like if the external USB3 chips selected weren't the best).

But it's possible they might be equal in terms of running
a given processor at stock speeds.

But you'll have to fill me in on what your expectations are.

If you needed lots of PCI Express bandwidth, then the 990FX
is probably a good way to get it. You pay for it, with
a little bit extra Northbridge power usage.

The motherboard reputations aren't markedly different.
I think the most expensive board got a few more low
ratings, because when an expensive board fails expectations,
people usually judge it harshly. When I bought a $65 motherboard,
nobody really hated that one, because, well, it was only
$65, and what do you expect for $65. And that board
still works :-)

Paul


Thanks (Guru Paul), so far, here is the components list ...

- ASUS M5A99X Evo - AM3+ - 990X - ATX DDR3 2133 Motherboards [under
consideration]
- G.SKILL Ripjaws X Series 16GB (4 x 4GB) 240-Pin DDR3 1600 (PC3 12800)
[under consideration]
- AMD Phenom II X4 [under consideration; will run processor at stock
speeds]
- Sapphire 100315L Radeon HD 6850 Video Card [already own; will be
single video card system]
- OCZ ModXStream Pro 600W Modular High Performance Power Supply
[already own]
- Antec Three Hundred ATX Mid Tower Gaming Computer Case [already own]

Objective is getting the best bang for the buck.


The only USB3 I know of, with a few problems, is Etron brand.

http://forums.tweaktown.com/asrock/4...0-problem.html

The M5A99X uses an Asmedia USB3 chip (a company which as far
as I know, is a subsidiary of Asus).

M5A99X EVO:

990X (1x16 or 2x8 video config)
SB950 (6 SATA III, No USB3)
(2) JMB362 (2 SATA II each)
RealTek 8111E (Ethernet NIC)
RealTek ALC892 (As long as you get at least stereo sound, you win...)
(2) AsMedia USB3 (four ports total, two ports full bandwidth)
VIA 6308P Firewire (Best were TI brand, or Lucent/Agere/LSI)

Of your PCI Express slots, install the video card in the top
slot, leave the second video card slot blank (to preserve the x16
interface rate), then you can use the x4 black slot for things
like a RAID card perhaps.

So the only shortcoming, is whether you consider the
video card slot running at x8 to be a problem or not.
x8 at PCI Express Rev2.0 rates, is 4GB/sec (8 lanes
times 500MB/sec transfer rate).

Check the reviews, see if the board has problems at higher
memory clock speeds, and perhaps you have a winner. That
board is certainly cheaper than the others. And the chipset
will run cooler.

With regard to the RAM, and how I'd run it, I'd buy the 4x4GB
kit (because DDR3 is cheap, but the price will rise as one
of the memory companies just got bought out). I'd operate
the motherboard with just two sticks (8GB). Then keep the
other two sticks as spares. Leaving two slots blank, improves
cooling around the memory slots. If you have a problem with
the 8GB, you just swap in the other pair. No downtime.

I bought a set of 8 DIMMs once, and three have failed.
Leaving me with five good ones :-)

The last RAM I bought, with zero failures, was in the
FPM/EDO era. Where it used to cost $600 to fill the computer
with RAM. RAM just doesn't hold up any more.

Paul


Thanks (Guru Paul), regarding USB3, I had USB3 issues with
my Asus laptop and had to downgrade the only USB3 port to use USB2.
Luckily, I don't own many USB3 devices yet. Perhaps,
USB3 is a general issue (with Asus and other brands)?

Not sure I understand this part ...

So the only shortcoming, is whether you consider the
video card slot running at x8 to be a problem or not.
x8 at PCI Express Rev2.0 rates, is 4GB/sec (8 lanes
times 500MB/sec transfer rate).

Is the video card being restricted (hopefully not)?
I don't play games much but do plan to watch videos.
How much better will the Sabertooth be?

Great idea about the RAM (and using only 2 slots first).

Check the reviews, see if the board has problems at higher
memory clock speeds, and perhaps you have a winner. That
board is certainly cheaper than the others. And the chipset
will run cooler.

I tend to run things at stock speeds so no overclocking issue?

Adam wrote:


Not sure I understand this part ...

So the only shortcoming, is whether you consider the
video card slot running at x8 to be a problem or not.
x8 at PCI Express Rev2.0 rates, is 4GB/sec (8 lanes
times 500MB/sec transfer rate).

Is the video card being restricted (hopefully not)?
I don't play games much but do plan to watch videos.
How much better will the Sabertooth be?

Great idea about the RAM (and using only 2 slots first).

Check the reviews, see if the board has problems at higher
memory clock speeds, and perhaps you have a winner. That
board is certainly cheaper than the others. And the chipset
will run cooler.

I tend to run things at stock speeds so no overclocking issue?


There are two decent PCI Express slots on the M5A99X EVO.

If you insert a video card in the upper slot, and place *no card*
in the second slot, the video card runs x16.

x16
none

If you were to plug an x1 TV tuner card into the second video
card slot, that would immediately cause the top video card
slot to run at x8.

x8
x8 --- I just plugged my TV tuner card in...

Some people care about that, but I don't. x8 should still be
enough. But some people don't like it.

So if you leave the second video card slot blank, then the top
slot continues to run x16. A gamer might like it this way.

x16
none

The third slot, is permanently wired x4. Even though the
slot is x16 in size, only x4 of the lanes are wired. And you
can visually see this, in motherboard pictures, by counting
the ceramic coupling capacitors next to the video slot.
A x16 capable slot, would have at least 16 "blobs" adjacent
to the slot. An x8 capable slot, at least 8 blobs. And so on.
The x16 slot with x4 wiring, would have 4 "blobs" next to it.

http://www.ixbt.com/mainboard/asus/m5a99x-evo/board.jpg

(Slot wiring circled...)

http://img713.imageshack.us/img713/9...iringcheck.gif

Pinout of PCI Express, so you can see why I'm circling those things.

http://media.bestofmicro.com/A/L/101...e-slot-big.gif

The PCI Express lanes are capacitively coupled. Which is why
those blobs are present. The capacitors must be placed, within
a certain distance of the slot, so they don't typically appear
at arbitrary spots. And since PCI Express lanes are bidirectional
(separate pair of TX wires, from separate pair of RX wires),
the other matching "blobs" are on the video card end, near the GPU.

PCI Express host --- cap --------------------- PCI Express
--- cap --------------------- peripheral card

--------------------- cap ---
--------------------- cap ---
Each pair of
wires = 500MB/sec

The PCI Express is "full duplex", meaning the card can talk to
the processor, at the same time as the processor is sending
something to the card.

Paul

"Paul" wrote in message
...
Adam wrote:


Not sure I understand this part ...

So the only shortcoming, is whether you consider the
video card slot running at x8 to be a problem or not.
x8 at PCI Express Rev2.0 rates, is 4GB/sec (8 lanes
times 500MB/sec transfer rate).

Is the video card being restricted (hopefully not)?
I don't play games much but do plan to watch videos.
How much better will the Sabertooth be?

Great idea about the RAM (and using only 2 slots first).

Check the reviews, see if the board has problems at higher
memory clock speeds, and perhaps you have a winner. That
board is certainly cheaper than the others. And the chipset
will run cooler.

I tend to run things at stock speeds so no overclocking issue?


There are two decent PCI Express slots on the M5A99X EVO.

If you insert a video card in the upper slot, and place *no card*
in the second slot, the video card runs x16.

x16
none

If you were to plug an x1 TV tuner card into the second video
card slot, that would immediately cause the top video card
slot to run at x8.

x8
x8 --- I just plugged my TV tuner card in...

Some people care about that, but I don't. x8 should still be
enough. But some people don't like it.

So if you leave the second video card slot blank, then the top
slot continues to run x16. A gamer might like it this way.

x16
none

The third slot, is permanently wired x4. Even though the
slot is x16 in size, only x4 of the lanes are wired. And you
can visually see this, in motherboard pictures, by counting
the ceramic coupling capacitors next to the video slot.
A x16 capable slot, would have at least 16 "blobs" adjacent
to the slot. An x8 capable slot, at least 8 blobs. And so on.
The x16 slot with x4 wiring, would have 4 "blobs" next to it.

http://www.ixbt.com/mainboard/asus/m5a99x-evo/board.jpg

(Slot wiring circled...)

http://img713.imageshack.us/img713/9...iringcheck.gif

Pinout of PCI Express, so you can see why I'm circling those things.

http://media.bestofmicro.com/A/L/101...e-slot-big.gif

The PCI Express lanes are capacitively coupled. Which is why
those blobs are present. The capacitors must be placed, within
a certain distance of the slot, so they don't typically appear
at arbitrary spots. And since PCI Express lanes are bidirectional
(separate pair of TX wires, from separate pair of RX wires),
the other matching "blobs" are on the video card end, near the GPU.

PCI Express host --- cap --------------------- PCI Express
--- cap --------------------- peripheral card

--------------------- cap ---
--------------------- cap ---
Each pair of
wires = 500MB/sec

The PCI Express is "full duplex", meaning the card can talk to
the processor, at the same time as the processor is sending
something to the card.

Paul


Thanks (Guru Paul), I just canceled my order for M5A99X EVO since
I would like a motherboard with more room for growth (or more PCI Express
slots).
Any CPU/motherboard combo suggestions?

Adam wrote:



Thanks (Guru Paul), I just canceled my order for M5A99X EVO since
I would like a motherboard with more room for growth (or more PCI Express
slots).
Any CPU/motherboard combo suggestions?

Without spending any time on it, this is the "most
PCI Express" I could find.

http://www.newegg.com/Product/Produc...82E16813128508

Note that it still uses the 990FX chipset. I think that chipset
has max total, about 42 lanes or so. Even the official looking
diagrams on the web, aren't complete.

The thing is, you can "fan out" lanes, but the max bandwidth
available doesn't change.

Say, for example, I do this.


x16 ----- Switch ---- x16 (card)
host Chip ------ x16 (card)

If both cards start transferring at the same time, each will
average x8 transfer rate. You cannot make something from nothing.

So when the chipset starts with 42 lanes, you cannot use chips
downstream of that, to make more bandwidth. The number of lanes
may *seem* larger, but depending on the transfer conditions,
the average rates achieved on the cards are still influenced
by the "narrowest piece of pipe".

To get a summary of the wiring pattern there, we don't trust
the Newegg table. This calls for the motherboard manual.

ftp://download.gigabyte.ru/manual/mb...0fxa-ud7_e.pdf

And even that might not be enough.

This is the block diagram. The official diagram is missing a
detail. This is my best guess now. I got a double-check
on ALink from here.

http://compare-processors.com/wp-con...chitecture.png

CPU
|
| 6.4GT/sec * 2bytes/T = 12.8GB/sec
|
Northbridge --- x16 ---- slot
| 990FX ---- slot
| --- x16 ---- slot
| ---- slot
|
| ---- x6 (flexible)
|
| ALink 2GB/sec
|
Southbridge ---- x4 (flexible)
SB950

The first thing to notice in such a diagram, is the CPU
connection to the outside world, is limited by Hypertransport.
Now, the claim I see, is the current transfer rate is 6.4 giga-transfers
per second. And that bus is 16 bits or 2 bytes wide. So the processor,
when sending bus traffic in one of the directions, cannot
exceed 12.8GB/sec when doing so. If I take 12800 and divide
by the 500 per PCI Express lane, that equals 25.6 lanes. That
means, the bottom part of the diagram has 42 lanes, but the
processor "bottleneck" supports at maximum 25.6 worth.

The second bottleneck, is the ALink. There are 4x500 for the
four PCI Express lanes off the Southbridge. But, there are
other "loads" on the Southbridge, such as your SATA drives.
Say, for example, you start a read on your 550MB/sec SATA III
SSD, at the same time as the x4 on the side are doing something.
There is a small chance of a bottleneck there.

When there is a bottleneck, nothing breaks, it just runs
slower. Like, when you step on a hose, and there is a lesser
trickle of water from the hose nozzle.

The impressive motherboard above, has the same restriction
as the motherboard you were just looking at.

Two video cards Two video cards
and two blanks and two TV tuners
-------------- -----------------

x16 x8
None x8 --- just installed Tuner

x16 x8
None x8 --- just installed Tuner

So that covers the restrictions on four of the slots. It
has twice as many slots for video, as the cheaper motherboard,
but the same style of restriction when all four have something
plugged in.

Now, try to figure out what remains. There are five
PCI Express peripheral chips. We have x6 left on top,
x4 left on the bottom. 10 - 5 = 5 left. Yet, there
are two x4 PCI Express slots, for a total of 8 lanes.
That means those 8 lanes can't be "real".

The Gigabyte diagram says something like this, but
there isn't a "switch" shown feeding the two x4 slots.

NB x6 --- x1 Etron EJ168 USB3
--- x1 88SE9172
--- x4 ------------------ switch --- x4
--- x4

SB x4 --- x1 Etron EJ168 USB3
--- x1 88SE9172
--- x1 RealTek RTL8111E NIC
--- x1 (unused???)

Notice that the two x4 slots, are sharing. If, for
some reason, one wants to run x4, it can. But if both
start transferring at the same time (unlikely, actually),
then they'd be limited to x2 each.

So even a fancy board, using the best (42 lane) chipset
on AMD you can find, is left wanting in places. But
at least you can say, "two video cards can be run
at x16 each". Subject to the bottleneck where the CPU
connects to things. So each card can have 6.4GB/sec average,
if both were transferring at the same time (say, some
Crossfire operation).

HTH,
Paul