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Old November 13, 2008, 11:05 PM
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Default Fix seems to have been discovered on the latest's wu's

Alright so i took this straight of the Folding @ home website.

Quote:
Engineers at NVIDIA (notably Scott LeGrand) have come up with a theory for the EUE's seen in core 1.15 (and a few others in the 1.15 to 1.18 range) on certain hardware. They found that this core had code optimizations that drove the GPU so hard that it would draw a lot more electricity (one sign of this was running hotter). In some boxes, this was too much electricity and this lead to numerical instabilities. When the same machine was given a beefier power supply, the problem went away.

We've been told that 8800's require 600W power supplies, but we're finding that even a little bigger (eg at least 650W) is important to leave some room for error. We are working to see if there is some way to detect this issue in software, but for now, if you're getting EUE's on the NV GPU client, this is something to consider.

By the way, this will be very important for us to consider future code optimizations. NV core v1.19 removed some optimizations to solve this problem, but there are many cards which would run fine w/this more optimized code. If we can find a way to detect whether the card can draw enough power, we may be able to choose different code paths to allow for greater optimization for cards which can handle it.

We're still looking into this. For now, if you're seeing issues with your card, please consider trying out a bigger power supply. We will continue to look to see if this is indeed the problem and what we can do to help the situation such that the code runs stably on all machines.
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Old November 13, 2008, 11:06 PM
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Alright i post this cause who here thinks this is utter rubish??? i mean most of us do not use cheap psu's or low powered psu's. Please correct me if im wrong but with my cpu downclocked to 1.4ghz can my videocard still use 500-600 watts?? it seems kind of impossible? I mean dont get me wrong theres a lot of people with cheap psu's out there but theres a lot of people with quality high powered psu's who were having the same problem reading thru the forums.

I think this is a half- baked answer from nvidia. Please leave yer 2 cents thankyou.
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Intel Xeon E3110 @ 3.0ghz
XFX 8800 GT Alpha Dog Edition
Asus P5Q-E
Mushkin Ascent Redline 8000 4gb DDR2 @ 1066 5-5-5-15 2.05v
OCZ 600W GameXstream
Seagate 7200.11 500gb
Seagate 7200.10 320gb
Antec Spot Cool
Logitech X-230
Samsung 32" 720P HDTV



Coolermaster Cosmos S/
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Old November 14, 2008, 05:31 AM
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It's indeed a half-baked answer but this doesn't stop the fact that they fixed the issue by swapping the PSU, hence the original thread. It's not a end-all solution and people came up with much better explanations. The strongest possibility is the memory bus width since we notice that the 8600GT is really affected by the issue and the larger the memory bus, the lesser the impact until it's gone on the GTX 2xx series.

At least, what Scott said is that the problem is reproductible in laboratory so they can now work on a fix (in the programming world, to create a fix, you first need to make the problem reproductible, what they failed to do until now).
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Old November 14, 2008, 03:26 PM
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My System Specs

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Since the 1.15 core was so highly optimized it's possible any weak point in a system would cause an EUE not just the PSU. Its unfortunate they had to force the 1.19 core on us since my 9800GTX+'s were getting less than one EUE a day...
On a side note my EUE rate seemed to drop slightly when I increased my Ram speed from 800 to 890 MHz, I was going to test it at a higher clock speed but they forced the 1.19 core ah.. upgrade...
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Old November 14, 2008, 05:32 PM
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yea my ppu has fallen down im going to take a break for a bit till they fix it. Well hopefully they can solve the answer instead of blaming the power supply i think a 600 watt power supply is more then plenty for one single 8800gt with the cpu underclocked i cant imagine it taking that much. Only time will tell....
__________________
Intel Xeon E3110 @ 3.0ghz
XFX 8800 GT Alpha Dog Edition
Asus P5Q-E
Mushkin Ascent Redline 8000 4gb DDR2 @ 1066 5-5-5-15 2.05v
OCZ 600W GameXstream
Seagate 7200.11 500gb
Seagate 7200.10 320gb
Antec Spot Cool
Logitech X-230
Samsung 32" 720P HDTV



Coolermaster Cosmos S/
Swiftech Mcp655/ MCR-320-QP/ 6X Noctua NF-P12'S/ Swiftech Apogee GT/ Swiftech Mcw-60/ Swiftech Micro-Res.

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