I bought an EVGA 8400GS PCI video card to give my little CUDA machine a boost. It seems to be running very slow - takes about 2 and a half times as long to crunch an equivalent unit as the 8600GT PCIE card in the same machine. 2hrs 15min as against 40 min for a 38 credit (validated value) unit.

What crunching times are others getting out of an 8400 and is the slowness due to the card or is it the PCI bus ?

Brodo

I think I've answered my own question. Was running BOINC 6.4.5 when I made the original post. Have just updated to 6.6.20. This verson tells me the 8600GT rates at 14 GFlops and the 8400GS only rates at 4 GFlops.

How does 4 GF's compare to the PCIE version of the 8400 card ? Anyone know ?

[edit] Further to this, Has anyone tried the Sparkle 9400 PCI card discussed on these boards a couple of weeks ago ? If so could you please post your results [/edit]

Brodo

My Palit 9600gt is rated at 37gflops. I dont know how much lower the 8600gs would be.
My 9600gts do Cuda in around 25 mins,with .13 cpu usage.
Dave

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Thanks for the info but I'm really after figures for PCI bus video cards rather than PCIe cards. Unless it's an 8400 so I can get a direct comparison between the PCI and the PCIe versions.

I thought an 8400 was capable of better than 4GFlops ? Would fitting a dummy plug to the monitor o/p help?

Brodo

Hi, I have 1 QUAD 6600 with a 8500GT, estimated 5GFLOP's and a QX9650 with a 9800GTX, estimated 84GFLOP's.
Both PCI-E x16, which is a must, considering bandwhith
Don't expect much from PCI cards, as only the bus is a bottleneck, AGP should do enough througput.

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... Don't expect much from PCI cards, as only the bus is a bottleneck, AGP should do enough througput.

And AGP is asymmetric. CPU -> GPU is fast-ish but the return trip is painfully slow.

Happy crunchin',
Martin

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25/04/2009 01:44:16 CUDA device: GeForce 8500 GT (driver version 18250, CUDA version 1.1, 256MB, est. 5GFLOPS)

PCI-E bus here

According to nVidia documentation, brodo's 8400GS has the same number of processing units (shaders), running at the same speed, as Raistmer's 8500 GT, but only half the internal memory bandwidth. Doesn't say anything about the external (bus) bandwidth, though.

Oh Well - it looka like my 8400GS compares pretty well then as far as GFlops goes. I don't expect it to be as fast as a PCIe unit but I would like to get an idea of how much the performance drops compared to PCIe.

@ Raistmer and Fred. What crunching times are you getting out of your 8500's ? My 8400 is taking around 1.5 to 2.5 hours for a "typical" unit and about 4.5 hrs for a VLAR. I don't mind the VLAR time, it's still quicker than the P4 that's driving it. :-)

Brodo

Thanks for sharing this Brodo. I thought PCI CUDA was a dead subject months ago.

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Thanks for sharing this Brodo. I thought PCI CUDA was a dead subject months ago.

I'm interested because I see it as a cheap upgrade to an old box. It may also be of interest to anyone else still running a P4 who would like a bit more grunt but doesn't want to shell out for a new system or those who MoBo's only have one PCIe slot.

Since I upgraded to 6.6.20 I can now run units on the CPU as well. With the 2 CUDA cards and using hyperthreading I now crunch 4 units at once. The PCIe 8600GT takes approx 45 mins/unit, the PCI 8400GS takes approx 1.5 hrs/unit and AK_v8 on the 2 virtual CPU's around 5-6 Hrs/unit This gives the potential for an RAC of just above 2000 (up from 600 with the naked P4). Not bad for a P4 sytem and an outlay of around $200 (less if you use $US).

I'd like to try the Sparkle 9400 PCI card but they're only available in the US and New Egg doesn't take credit card or PayPal for overseas orders, the company I deal with in The States doesn't sell it.

Brodo

I'm interested because I see it as a cheap upgrade to an old box. It may also be of interest to anyone else still running a P4 who would like a bit more grunt but doesn't want to shell out for a new system or those who MoBo's only have one PCIe slot.

I agree, and was the main reason I was interested in it a few months ago as well. I have several older AMD systems that could benefit from a PCI CUDA card ;-)

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I'm interested because I see it as a cheap upgrade to an old box. It may also be of interest to anyone else still running a P4 who would like a bit more grunt but doesn't want to shell out for a new system or those who MoBo's only have one PCIe slot.

I agree, and was the main reason I was interested in it a few months ago as well. I have several older AMD systems that could benefit from a PCI CUDA card ;-)

If your interested in how things go, Keep an eye on this computer 4735693

Brodo

I recently added a 8600gts 256ddr3 PCI card to an old system, the highest PCI card i could find, est. 17GFLOPs. found it on newegg or tigerdirect for $50. runs a little warm for me, about 80C, but i have an upgraded cooler on order for it from tigerdirect: Thermaltake SOrb, hope that helps you. It has recently improved my RAC.

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