Dual channel DDR ?

Sorry if this is a repost , just found groups.
ABIT NF7-S mobo
2 x Crucial 333 2.5 CAS DDR DIMMS

lots of questions...................

Is Dual Channel DDR a feature of the Motherboard or, of the memory sticks ,
or of both? , For example would dual channel DDR work with 2 standard DDR
333 / 400 sticks ?
Does the memory system need to be running at 400 before dual channel is
activated ?
Is there a program to check if its on or not ?
Are these Dual channel memory stick kits advertised just two matched
standard DDR DIMMS ?

Ive looked on the ABIT website and there is no mention of needing different
or special memory when using the NF7 boards
I'm getting a slightly lower 3Dmark score than equivalent systems and need
to eliminate this from the equation.
Thanx in advance

_____________________________________

Matthew Purves , (Deadly_M)
www.DeadlyM.com

dual channel is a feature of the mobo/chipset. the same DDR ram is involved
in dual channel or regular. to my knowledge, the speed that the DDR is
running at has nothing to do with it. in all cases I am familiar with, dual
channel is enabled when an even number of sticks of DDR ram are installed
and the memory is a close enough match that the bios enabled the dual
channel mode.

many a ram vendor is charging a premium for matched dual channel sticks when
in reality, as long as the ram is the same type and rating, it will work in
dual channel mode.

--

Thomas Geery
Network+ certified

ftp://geerynet.d2g.com
ftp://68.98.180.8 Abit Mirror ----- Cable modem IP
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"Deadly_M" wrote in message
...
Sorry if this is a repost , just found groups.
ABIT NF7-S mobo
2 x Crucial 333 2.5 CAS DDR DIMMS

lots of questions...................

Is Dual Channel DDR a feature of the Motherboard or, of the memory sticks
,
or of both? , For example would dual channel DDR work with 2 standard DDR
333 / 400 sticks ?
Does the memory system need to be running at 400 before dual channel is
activated ?
Is there a program to check if its on or not ?
Are these Dual channel memory stick kits advertised just two matched
standard DDR DIMMS ?

Ive looked on the ABIT website and there is no mention of needing
different
or special memory when using the NF7 boards
I'm getting a slightly lower 3Dmark score than equivalent systems and need
to eliminate this from the equation.
Thanx in advance

_____________________________________

Matthew Purves , (Deadly_M)
www.DeadlyM.com

Deadly_M wrote:
Sorry if this is a repost , just found groups.
ABIT NF7-S mobo
2 x Crucial 333 2.5 CAS DDR DIMMS

lots of questions...................

Is Dual Channel DDR a feature of the Motherboard or, of the memory sticks
, or of both? , For example would dual channel DDR work with 2 standard
DDR 333 / 400 sticks ?

It is solely a feature of the chipset, you do not need "special" RAM. There
is also no such thing as Dual Channel RAM.

You will require 2 or 3 DIMMS.

Does the memory system need to be running at 400 before dual channel is
activated ?


Dual Channel can operate at ny frequency supported by the chipset, on your
board I suspect thats anywhere from 133 to 200MHz.

Is there a program to check if its on or not ?

Later BIOSs for the A7N8X tell you on boot what mode it is in, I susoect
that the nVidia Utility lets you know too.

Are these Dual channel memory stick kits advertised just two matched
standard DDR DIMMS ?

Yes.

Ive looked on the ABIT website and there is no mention of needing
different or special memory when using the NF7 boards
I'm getting a slightly lower 3Dmark score than equivalent systems and need
to eliminate this from the equation.

Well your memory timings will play a factor in benchmark speeds. I'm
running 7-2-2-2 and get pretty good benchmarks for my system.

Ben
--
A7N8X FAQ: www.ben.pope.name/a7n8x_faq.html
Questions by email will likely be ignored, please use the newsgroups.
I'm not just a number. To many, I'm known as a String...

"Deadly_M" wrote in message
...
Sorry if this is a repost , just found groups.
ABIT NF7-S mobo
2 x Crucial 333 2.5 CAS DDR DIMMS

lots of questions...................

Is Dual Channel DDR a feature of the Motherboard or, of the memory sticks
,
or of both? , For example would dual channel DDR work with 2 standard DDR
333 / 400 sticks ?

Yes, I'm running with two sticks of OCZ rev2 PC3200 vey nicely thank you!

Does the memory system need to be running at 400 before dual channel is
activated ?

AFAIK, nope!

Is there a program to check if its on or not ?
Are these Dual channel memory stick kits advertised just two matched
standard DDR DIMMS ?

Probably, as long as they are nearly identical you should be able to run
dual channel

Ive looked on the ABIT website and there is no mention of needing
different
or special memory when using the NF7 boards
I'm getting a slightly lower 3Dmark score than equivalent systems and need
to eliminate this from the equation.
Thanx in advance

If you want to run dual channel on the NF7-S then pop your sticks of ram
into slots 1 & 3!
You will know that dual channel is operating as it will inform you during
POST that dual channel is active.
You dont say what cpu/gfx card you are using which obviously affects your
3dM score, as do various bios settings.

chris

_____________________________________

Matthew Purves , (Deadly_M)
www.DeadlyM.com

On my NF7-S ver. 2.0 mobo, on the first screen (where it also lists what
devices, if any, were discovered on the IDE ports) during bootup, it will
display whether or not dual channel memory got enabled. That's how I
verified that it was working. You have to insert 2, and only 2, memory
sticks where each is in a different bank (i.e., each will use a separate
64-bit memory controller). If you install 1, 3, or more sticks, I don't
think dual-channel gets enabled. It has to be just 2 sticks you install.

I didn't bother paying a premium for a matched pair of memory sticks (I hear
you must do this for RAMBUS). Just buy 2 of the *same* brand and size
memory sticks. I believe there are some restrictions on what architecture
(or organization) can be used for the memory. For example, while Abit
doesn't mention it on their web pages to describe their mobos nor in their
manual (for my NF7-S), MSI mentions(http://snipurl.com/376y):

"Note: nForce2 does NOT supports x4 memory device. 1GB can be made by other
density of dram chip such as x 8, x16."

It is unclear if this restriction applies only when you want to install a
total of 1GB, or maybe more, or if it applies to whatever memory sticks you
install. I think the xN spec means how many columns wide, or density, each
chip on the PCB will address, but someone more expert on memory can probably
indicate what it means. I'm still trying to figure out what CL=2.5-6-3-3
means (the 2.5 is the CAS delay but I don't know the others). I figure if
the restriction applies to MSI mobos that use the nForce chipset then it
probably applies to other brand mobos that use the same chipset.

I bought a pair (but not matched) of Geil 256MB PC3200 CAS2.5 x8 sticks
(http://snipurl.com/geil256x8) from newegg.com for $88 a couple weeks ago
and now they're down to $78 ($39 each). Geez! I like that they came with a
heat spreader should I ever decide to overclock (might try that later). The
specs at Geil show CL=2.5-6-3-3 but I'll have to check my BIOS because I
think it selected 7-4-4 (forgot what it picked for CAS) so I might be able
to speed up the memory a wee bit by matching the BIOS to the faster spec
noted by Geil (and without overclocking), but then memory detect in BIOS is
set to Auto rather than by the separate SPD selection (serial presence
detect, provided by non-volatile RAM on the memory stick). Maybe using SPD
will make the BIOS pick the shorter specs; otherwise, I'll have to set them
manually and see if the computer remains stable.

"*Vanguard*" wrote in message
news:SniIb.691369$HS4.4896781@attbi_s01...
On my NF7-S ver. 2.0 mobo, on the first screen (where it also lists what
devices, if any, were discovered on the IDE ports) during bootup, it will
display whether or not dual channel memory got enabled. That's how I
verified that it was working. You have to insert 2, and only 2, memory
sticks where each is in a different bank (i.e., each will use a separate
64-bit memory controller). If you install 1, 3, or more sticks, I don't
think dual-channel gets enabled. It has to be just 2 sticks you install.

Three sticks will also work in dual channel mode on the NForce chipset. For
example, many people start with two 256-meg sticks and later add a 512-meg
stick in the last slot. It will still operate in dual-channel mode.

snip

I'm still trying to figure out what CL=2.5-6-3-3
means (the 2.5 is the CAS delay but I don't know the others).

Best place to go is the bios guide at www.rojakpot.com It explains memory
timings and all the other arcane settings the manual doesn't cover.

"Skid" wrote in
news:RGiIb.704298$Fm2.606265@attbi_s04:


Three sticks will also work in dual channel mode on the NForce
chipset. For example, many people start with two 256-meg sticks and
later add a 512-meg stick in the last slot. It will still operate in
dual-channel mode.

This is exactly what I've done, courtesy of Father Christmas I am now
blessed with a 512 meg stick and the two 256's I had earlier. The 256's
share one memory controller, and the 512 has the other so it works out
balanced. Memory performance appears not to have suffered from the addition
of another DIMM (on my 8RDA+ anyway).

"Skid" wrote in message
news:RGiIb.704298$Fm2.606265@attbi_s04...
"*Vanguard*" wrote in message
news:SniIb.691369$HS4.4896781@attbi_s01...
On my NF7-S ver. 2.0 mobo, on the first screen (where it also lists what
devices, if any, were discovered on the IDE ports) during bootup, it
will
display whether or not dual channel memory got enabled. That's how I
verified that it was working. You have to insert 2, and only 2, memory
sticks where each is in a different bank (i.e., each will use a separate
64-bit memory controller). If you install 1, 3, or more sticks, I don't
think dual-channel gets enabled. It has to be just 2 sticks you
install.

Three sticks will also work in dual channel mode on the NForce chipset.

Is that true for MSI K7N? It uses the nForce 2 chip set.

For
example, many people start with two 256-meg sticks and later add a 512-meg
stick in the last slot. It will still operate in dual-channel mode.


snip

I'm still trying to figure out what CL=2.5-6-3-3
means (the 2.5 is the CAS delay but I don't know the others).

Best place to go is the bios guide at www.rojakpot.com It explains memory
timings and all the other arcane settings the manual doesn't cover.

"fj" wrote in message
...
"Skid" wrote in message
news:RGiIb.704298$Fm2.606265@attbi_s04...
"*Vanguard*" wrote in message
news:SniIb.691369$HS4.4896781@attbi_s01...
On my NF7-S ver. 2.0 mobo, on the first screen (where it also lists
what
devices, if any, were discovered on the IDE ports) during bootup, it
will
display whether or not dual channel memory got enabled. That's how I
verified that it was working. You have to insert 2, and only 2,
memory
sticks where each is in a different bank (i.e., each will use a
separate
64-bit memory controller). If you install 1, 3, or more sticks, I
don't
think dual-channel gets enabled. It has to be just 2 sticks you
install.

Three sticks will also work in dual channel mode on the NForce chipset.

Is that true for MSI K7N? It uses the nForce 2 chip set.

Yes. The NForce boards work that way, either two or three sticks will work
in dual channel mode.

The Intel boards, 865 and 875 chipsets, require either two or four sticks
for dual channel, and will not work in dual channel with three.

"Skid" wrote in message
news:BsGIb.16625$I07.47556@attbi_s53...

"fj" wrote in message
...
"Skid" wrote in message
news:RGiIb.704298$Fm2.606265@attbi_s04...
"*Vanguard*" wrote in message
news:SniIb.691369$HS4.4896781@attbi_s01...
On my NF7-S ver. 2.0 mobo, on the first screen (where it also lists
what
devices, if any, were discovered on the IDE ports) during bootup, it
will
display whether or not dual channel memory got enabled. That's how
I
verified that it was working. You have to insert 2, and only 2,
memory
sticks where each is in a different bank (i.e., each will use a
separate
64-bit memory controller). If you install 1, 3, or more sticks, I
don't
think dual-channel gets enabled. It has to be just 2 sticks you
install.

Three sticks will also work in dual channel mode on the NForce
chipset.

Is that true for MSI K7N? It uses the nForce 2 chip set.

Yes. The NForce boards work that way, either two or three sticks will work
in dual channel mode.

The Intel boards, 865 and 875 chipsets, require either two or four sticks
for dual channel, and will not work in dual channel with three.


Do I need to make sure the organization of the memory chips is the same?
I've heard that DIMM's can use chips that are x1, x4, x8.

Thanks