core slowdown threshold

I tried 80mm and 120mm fans in various positions around the card.. negligible effect. And as you recall, I tried blocking the fan and heating up the card really good to see the effect.. it was still able to do 425/950 sometimes without throttling.. And I ran about half dozen 410/936 before throttling (maybe even bit higher than avg)

I recently tried even thicker shims (~10 tau vs 5 tau before). Result is about same to without shims.

I'm looking around town for some high quality capacitors, and will see what that will result in.

PS: although not sure way to eliminate possibility, I concluded that since throttle happens at CPU=800, =1800, =2400, and =2600 (with 5 drives!), and even able to get clean runs at 2600, that power supply problem is not an issue.

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Quote:

Originally Posted by ***Deimos***

On the top graph, I first ran without modifying clocks (BIOS values), then clock to 425/950 to simulate throttling.

Once again, I know about force-perf-level, or setting all clocks same in rivatuner, or setting all clocks same in BIOS. The same thing happens regardless. Either the card runs at full performance, or it runs at nearly identical performance to GPU=300Mhz (where would it get this clock speed from?), even though rivatuner continuously shows the same high overclock (ie 410), or terrible artifacts. When clocks are different, and there is no force-perf level, artifacts ALWAYS correspond to it switching to 300Mhz, and sometimes to 400 (using your bios).

I would be happy to let 425/950 go. I have nearly come full circle, and have re-investiaged the famous 6800/NF3 connection (yeah, I have NF3). So, I re-enabled FAST WRITES in mobo BIOS. Now, it might be just a coincidence, but anything north of 370Mhz, causes stuttering, pausing, blank screen, and yes even artifacts. However, the strange thing is, when 3DMark05 run for first time (starting from 2D clock), it will blank screen/pause resume, then pause again etc... when you quit test, it clocks up to 410 (even though you're just on the desktop). Quick subsequent run (before it throttles back down), it doesnt pause/blank at the very beginning.. still happens later on though. But rivatuner shows that higher clock was used for the first little while until it pause/blank and there is corresponding throttle to either low-power 3D or 2D.

I went over all the 6800/NF3 "solutions" again to make sure I didn't miss something: AGPx4, AGP=55, AGP=75, sideband=off, user mipmap=off, blitting, aperature=32, aperature=512 (normally 256), lower RAM speed 10%, CPU at stock, CPU @ 800Mhz, loosen all RAM timings, ...

Only thing that "works" is fast-writes = off. However, I think its only lowering the occurance of the problem. Quite similar symptoms show up, but much more rarely with fast-writes off. So the only way to get consistenly 3D clocks is 370/740 with fast writes off (370+ and/or 800+ will sporadically cause throttling)

EDIT: I'm already on 4th power supply!! And, I'm still trying to get this card working on my brother's computer.. last time just installing the card messed up windows and his ati drivers really bad.. he had to reinstall windows :(

NF3 mobo's are legend for having "fastwrite" problems with Nvidia cards, so I would agree that it is best left disabled.

And as previously stated, when overclocked, occasional throttling to low power 3D levels is NORMAL and therefore to be IGNORED. The only throttling you should be concerned with is when it switches fully down to 2D (300) because of extreme overclocking/overloading abuse.

Bottom line is, if you don't ever want any kind of throttling, then don't overclock your card !!!

And, just for interest, I have a XFX6800le which is fitted with a NV5 (rev2) silencer and is fully unlocked to 16x1,6vp, and there are no artifact problems running with core at 1.3v and 425/920 !

Using those speeds and volts as a ref for all bioses, just did multiple runs of 3dmark05 using original LE bios, your NU bios and a asus GT 128 Mb agp bios, and found no problems with any of them. However, my 6800le appeared more stable with its original and the asus GT than it did when flashed with yours. And with all, temps maxed at around 40C ambient and 62C core. Also, the asus GT bios gave slightly better performance, 5205 as opposed to around 5180 for the other two. Was using 84.20 for all 3dmark05 testing. Also ran LUNA demo which is a good test of overclocked memory and found no problems with any bios, other than of course the fact that my 6800le with only 128mb DDR memory does not run as smoothly as my 6800gs which has 256mb DDR3.

Since it has been proven many times that not all bioses are the same, maybe you should now consider seeing if another bios can achieve better stability with your particular card??

And just in case you are interested, you will find xfx6800le and asus6800gt bioses which are modded to 410/900 linked below in the a68g4190.zip file.

EDIT:

And although you have used different PSU's, did you also remember to NEVER share the vga cards mollex'd supply line with any other dynamic devices, like CDROM,DVDROM, BURNERS or HDD's ?

video card always on different cable.
I learned that lesson long ago.

On each power supply I tried different molex connecters. Just as I thought I had better stability, it would crap out. I guess whether its failing every 15 min or every 50 min, its still failing.

I will check with those BIOS you posted, and try to see if it will help with throttling to 2D problem.