ECC memory in PCI-Express systems

[DonPMitchell]

We'd like to buy or build a machine with a lot of memory and a hot graphics card. Specifically, we want the new PCI-Express (925 chipset) and something like the ATI X800 XT card. But we also number crunch and want a lot of ram, maybe 4 Gb.

We believe this means the memory has to be ECC. Memory parity errors cause about 12 percent of system crashes on normal machines, and its a much bigger problem with a 2 or 4 Gb machine. But, all the offerings I see, like GamePC, Alienware, or the Dell XPS Gen 3, seem to take only non-ECC memory.

Looking at 925 motherboards, they all say "non-ECC", except the SuperMicro P8SAA. OK, can we really build our system with that board? What is troubling me are rumors that the 925 chipset, which is supposed to support ECC, doesn't really work right yet and cannot safely support ECC yet. Is that true?

Anyone know the real facts? Can we build a hot PCI-Express system with lots of ECC memory?

 

[DerwenArtos12]

Wow, the we thing is almost creepy. You do not need 4gigs of ECC ram. For one two gigs is plenty and ECC is more than not necessary. PCI-E isn't a bad idea but good luck trying to find all the parts you'll need. Mobo and CPU shouldn't be too tough but the PCI-E radeon will be a tough one. Also I would suggest the PCI-E 6800GT, save yous ome cash and get more than plenty of performance. I don't know if IT supports it or not But I haven't seen any DDR2 that isn ECC. God, I didn't even think of that yet, even 2 gigs of DDR2 is gonna cost a small fortune.

 

[DerwenArtos12]

This is about the best S775$280
Processor: 3.0E$228
512MB DDR-2 667$235x4=$940
Let's say you could get a PCI-E 6800GT for $450
WD 80Gb Sata HDD(I recomend Raid0)$72x2=144
NED Black DVD-RW$75

Total:$2117
Without a case because they can range from $20 to $400.

 

[DonPMitchell]

The "We" is is our company, sorry. I really do need lots of memory, it has to be ECC, doesn't matter what it costs. Maybe the answer is getting two computers, but now I want to understand the issue.

Does anyone know if there is a problem with the 925 chipset and ECC memory? It's supposed to, but even the Intel 925 motherboard says non-ECC only. And I found this article:

http://www.theinquirer.net/?article=16486

which seems to suggest that there is a problem that Intel has not fixed yet. But there is *one* motherboard from SuperMicro that says it takes ECC dimms. So what is the deal???

 

[o1die]

You might also want to research opteron systems. Some of their boards will take 4 gigs of ecc memory. Intel just updated the xeon cpu, and opteron is comparable or better in some benchmarks. Do some research; don't take my word for it.

 

[DonPMitchell]

Yes, the AMD offerings are very interesting. The big issue is whether they will support the latest high speed DirectX 9 boards, with texture memory bandwidths comperable to the PCI-Express.

 

[DonPMitchell]

Thank-you to Mike Magee for this:

http://developer.intel.com/design/pcn/MTHRBRD/D1042430.pdf

Looks like ECC does not work, but has been fixed for future batches of the motherboards.

 

[DerwenArtos12]

Ah, it is for a company, The only current PCI-E x16 boards I have seen are Intel P4, and they have 4 memory banks for up to 4 gigs of DDR2 Ram butI haven't seen 1 gig sticks of DDR2 and I haven't seen DDR2 that is ECC yet. The advantage of PCI-E when it comes to video cards i minimal at best. I would sugest you a dual opteron sstem with 2 gigs of memory per cpu and an AGP GeForce 6800GT.(I'll do another mock-up in a second post here in a minute)

 

[DerwenArtos12]

Tyan Thunder K8W$435
Opteron 242 1.6ghz x 2$223x2=$446
Buffalo DDR-3200 ECC 512mb x 8$109x8=$872
Let's say you could get a AGP 6800GT for $400
WD 80Gb Sata HDD(I recomend Raid0)$72x2=144
NED Black DVD-RW$75

Total is $2372, it's definatly faster and has twice as muchram and it's ECC.
once again no case for same reaason.

 

[SexyLady]

I dont know if this will take ECC but it takes both DDR2 AND DDR it is PICe LAG775 socket http://tw.giga-byte.com/MotherBoard/Products/Products_Spec_GA-8GPNXP%20Duo.htm it also has 2 10 base 1000 RJ45 connectors as well as wireless (quite a sweet little board i am running it at the moment)

OPPPS sorry its only the 915P chipset ... my bad

 

[DonPMitchell]

Derwen, many thanks. I appreciate the time you've taken.

The story about the 925 chipset is this: it was designed to support ECC, but that didn't work reliably until a product update *this* month. So beware not to get an old board if you want ECC.

I see that the dual-Xeon E7525 chipset also supports PCI-Express, as well as DDR2 memory with ECC. Our last main computer was dual Xeon, which is important for concurrent-software testing, but was disturbingly expensive. Here's a recent benchmark of 3.4 GHz dual Xeon versus dual Opteron 250:

http://www.gamepc.com/labs/view_content.asp?id=noconaopteron&page=1

What I found surprising was the effect of NUMA awareness in the operating system (64-bit WinXP) , which allowed the dual AMD architecture to grab enormous independant memory bandwidth. When that mattered, the AMD system did much better than the Intel system. Interesting.

 

[Vette73]

Originally posted by: DonPMitchell
Yes, the AMD offerings are very interesting. The big issue is whether they will support the latest high speed DirectX 9 boards, with texture memory bandwidths comperable to the PCI-Express.

The problem is there are no Video Cards that even use the speed of AGP 8X, let alone PCI-E 16x. Also the PCI-E boards/chipsets from intel have problems and are not 100%. Heck even the drivers are not really mature for PCI-E yet.

So if you are worried about stability I would look at a Opteron system. It supports Reg. ECC ram and has been out long enough to prove itself. Also since the Opteron has 64bit support you can run OVER 4 gig with a 64bit OS.

 

[DerwenArtos12]

Originally posted by: Marlin1975

Originally posted by: DonPMitchell
Yes, the AMD offerings are very interesting. The big issue is whether they will support the latest high speed DirectX 9 boards, with texture memory bandwidths comperable to the PCI-Express.

The problem is there are no Video Cards that even use the speed of AGP 8X, let alone PCI-E 16x. Also the PCI-E boards/chipsets from intel have problems and are not 100%. Heck even the drivers are not really mature for PCI-E yet.

So if you are worried about stability I would look at a Opteron system. It supports Reg. ECC ram and has been out long enough to prove itself. Also since the Opteron has 64bit support you can run OVER 4 gig with a 64bit OS.

Great point, PCI-E jsut made it to tha maket within the last month or so. If this computer is for a business then you need something reliable, opteron's have been around for quite awhile, they perfomr as well if not better and are very very reliable. I can give you a perfect example, my radeon x800pro has some horrible OGL problems with KOTOR because it is new and not yet full supported. There is an easy fix going around that you can use catalyst 4.2's ogl drivers to fix the problem but, it is a new technologie and won't work with the old drivers. I am basically SOL when it comes to playing KOTOR.