32/16GB of DDR2-533/667 ???

this is a motherboard memory specifications, do I read that as

up to 32 gig of ddr2 memory running at 533

or

up to 16 gig of ddr2 memory running at 667?


why would it have this limitation? I would think it wouldn't matter (to the
motherboard) what the speed was

thanks

Hank wrote:
this is a motherboard memory specifications, do I read that as

up to 32 gig of ddr2 memory running at 533

or

up to 16 gig of ddr2 memory running at 667?


why would it have this limitation? I would think it wouldn't matter (to the
motherboard) what the speed was

thanks


Did the specs say anything about number of DIMMs? Often mobos will only
handle a limited number of DIMMs at higher speeds? Has to do with length
of the memory busses involved.

On Thu, 12 Apr 2007 10:43:30 GMT, "Hank"
wrote:

this is a motherboard memory specifications, do I read that as

up to 32 gig of ddr2 memory running at 533

or

up to 16 gig of ddr2 memory running at 667?


why would it have this limitation? I would think it wouldn't matter (to the
motherboard) what the speed was

thanks



The same is true of all motherboards whether spec'd or not.
The more memory you install the lower the stability margin,
and if the margin drops low enough it will require reducing
the memory bus speed or raising the timings to retain
stability (and/or registered or buffered memory). However,
some boards conveniently avoid this by merely having too few
slots to install that much, or their bios logic
automatically changes the timings to compensate.

kony wrote:
On Thu, 12 Apr 2007 10:43:30 GMT, "Hank"
wrote:

this is a motherboard memory specifications, do I read that as

up to 32 gig of ddr2 memory running at 533

or

up to 16 gig of ddr2 memory running at 667?


why would it have this limitation? I would think it wouldn't matter (to the
motherboard) what the speed was

thanks



The same is true of all motherboards whether spec'd or not.
The more memory you install the lower the stability margin,
and if the margin drops low enough it will require reducing
the memory bus speed or raising the timings to retain
stability (and/or registered or buffered memory). However,
some boards conveniently avoid this by merely having too few
slots to install that much, or their bios logic
automatically changes the timings to compensate.

The OP may be referring to a 5000 series server motherboard, with
FBDIMM memory. FBDIMMs are serially connected, at extremely
high speed. They are effectively point to point. The second
FBDIMM in a channel is daisy chained to the first, meaning
there is the "thru-delay" via the AMB on the first module,
before you get to the second.

The serial interconnect on the FBDIMM, is synchronous to what
the memory chips are doing. If DDR2-667 memory is used,
the serial interconnect is at 12 x 333MHz, for a 4Gbit/sec
interconnect to controller or to the next FBDIMM.

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

I cannot figure out a reason why one of those would have
a stated capacity versus speed issue. Being fully buffered,
the motherboard cannot "see" the load from the memory chips
on the module. So it shouldn't matter. The Tyan advertising
seems to relate size to speed, but the Supermicro advertising
for similar products doesn't.

Tempest i5000XT (S2696)
http://www.tyan.com/product_board_spec.aspx?pid=43

"Maximum of 32/16GB of DDR2-533/667"

So it is still a mystery to me, why they state it that way.
And the user manual does not elaborate further on the issue.

Paul

Thanks , this is the system I'm thinking of putting together



TYAN S2696A2NRF (SATA) Dual Socket 771 Intel 5000X Extended ATX Server
Motherboard - Retail
Item #: N82E16813151048


SAMSUNG SpinPoint T Series HD501LJ 500GB 7200 RPM SATA 3.0Gb/s Hard Drive -
OEM

OCZ GameXStream OCZ700GXSSLI ATX12V 700W Power Supply - Retail
Item #: N82E16817341002


CHENBRO SR10769-BK Black 1.0 mm SECC Server Case - Retail

Crucial 2GB 240-Pin DDR2 FB-DIMM DDR2 667 (PC2 5300) ECC Fully Buffered
Server Memory Model CT25672AF667 - Retail




"Paul" wrote in message ...
kony wrote:
On Thu, 12 Apr 2007 10:43:30 GMT, "Hank"
wrote:

this is a motherboard memory specifications, do I read that as

up to 32 gig of ddr2 memory running at 533

or

up to 16 gig of ddr2 memory running at 667?


why would it have this limitation? I would think it wouldn't matter (to
the motherboard) what the speed was

thanks



The same is true of all motherboards whether spec'd or not.
The more memory you install the lower the stability margin,
and if the margin drops low enough it will require reducing
the memory bus speed or raising the timings to retain
stability (and/or registered or buffered memory). However,
some boards conveniently avoid this by merely having too few
slots to install that much, or their bios logic
automatically changes the timings to compensate.

The OP may be referring to a 5000 series server motherboard, with
FBDIMM memory. FBDIMMs are serially connected, at extremely
high speed. They are effectively point to point. The second
FBDIMM in a channel is daisy chained to the first, meaning
there is the "thru-delay" via the AMB on the first module,
before you get to the second.

The serial interconnect on the FBDIMM, is synchronous to what
the memory chips are doing. If DDR2-667 memory is used,
the serial interconnect is at 12 x 333MHz, for a 4Gbit/sec
interconnect to controller or to the next FBDIMM.

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

I cannot figure out a reason why one of those would have
a stated capacity versus speed issue. Being fully buffered,
the motherboard cannot "see" the load from the memory chips
on the module. So it shouldn't matter. The Tyan advertising
seems to relate size to speed, but the Supermicro advertising
for similar products doesn't.

Tempest i5000XT (S2696)
http://www.tyan.com/product_board_spec.aspx?pid=43

"Maximum of 32/16GB of DDR2-533/667"

So it is still a mystery to me, why they state it that way.
And the user manual does not elaborate further on the issue.

Paul

"Pen" wrote in message
...
Hank wrote:
this is a motherboard memory specifications, do I read that as

up to 32 gig of ddr2 memory running at 533

or

up to 16 gig of ddr2 memory running at 667?


why would it have this limitation? I would think it wouldn't matter (to
the motherboard) what the speed was

thanks


Did the specs say anything about number of DIMMs? Often mobos will only
handle a limited number of DIMMs at higher speeds? Has to do with length
of the memory busses involved.

here are the specs

Model
Brand TYAN
Model S2696A2NRF (SATA)
Supported CPU
CPU Socket Type Dual Socket 771
CPU Type Dual Intel Xeon
FSB 1333/1066MHz
Chipsets
North Bridge Intel 5000X
South Bridge Intel 6321ESB
Memory
Number of DDR2 Slots 8 x 240Pin
DDR2 Standard DDR2 667
Maximum Memory Supported 32/16GB of DDR2-533/667
Dual Channel Supported Four memory channels
ECC Supported Yes
Registered FBDIMM
Expansion Slots
PCI Express x16 1
PCI Express x4 2
PCI-X Slots (64-bit 133MHz) 2
PCI Slots 1
Storage Devices
PATA 1 x ATA 100 up to 2 Devices
SATA 6 x SATA II
SATA RAID 0/1/10/5
Onboard Video
Onboard Video Chipset None
Onboard Audio
Audio Chipset Realtek ALC888
Audio Channels 8 Channels
Onboard LAN
LAN Speed 10/100/1000Mbps
Second LAN Speed 10/100/1000Mbps
Max LAN Speed Dual 10/100/1000Mbps
Rear Panel Ports
PS/2 2
COM 1
LPT 1
USB 4 x USB 2.0
IEEE 1394 1 x IEEE 1394a
S/PDIF Out 1x Coaxial
S/PDIF In 1x Coaxial
Audio Ports 3 Ports
Onboard USB
Onboard USB 2x USB 2.0
Onboard 1394
Onboard 1394 1x 1394a
Physical Spec
Form Factor Extended ATX
Dimensions 13.0" x 12.0


the entire system I'm thinking of putting together


TYAN S2696A2NRF (SATA) Dual Socket 771 Intel 5000X Extended ATX Server
Motherboard - Retail
Item #: N82E16813151048


SAMSUNG SpinPoint T Series HD501LJ 500GB 7200 RPM SATA 3.0Gb/s Hard Drive -
OEM

OCZ GameXStream OCZ700GXSSLI ATX12V 700W Power Supply - Retail
Item #: N82E16817341002


CHENBRO SR10769-BK Black 1.0 mm SECC Server Case - Retail

Crucial 2GB 240-Pin DDR2 FB-DIMM DDR2 667 (PC2 5300) ECC Fully Buffered
Server Memory Model CT25672AF667 - Retail