I have a 6800GT AGP overclocked to 430/1160, and I can bench with it and stuff. The problem is that after a while the performance drops to below that of even stock speeds. How do you stop this from happening?
I think its overheating.. I have 350W enermax and no probs with my system. I think my system uses alot more power
It has a Zalman VF700 on it, and I've tested the thing with the case open and lying on its side. The temperature maxes out around 68-70C with the ATI Tool stress test running. My PSU has 21A on the 12V rail and it's an Antec so that should be fine. It will run the 1st round of 3DMark tests fine, but if I ask it to run each test more than once, it'll bring in an unusually low score. Similarly, with the 430/1160 overclock I get about 404FPS in the ATI Tool test, but if I stress it for a few min and then let it run passively again, I'll be getting around 130FPS. I've used Rivatuner's monitor to check that it doesn't underclock itself or anything as well. If overheating is the issue, are those symptoms normal?
From what it sounds like to me, your card is lacking something. If the problem persists in that it starts strong (first few tests, numbers are good) than I would have to eliminate that the card is malfunctioning.. Since you say that performance seems to get progressively worse, I beleive its some sort of power issue. Could be a heat issue, but at those temperatures I doubt it. May want to look into just how much power is coming down that 12v rail..
Typically when FPS performance markedly reduces after playing games for some time, it is due to the card's built-in throttling protection facility detecting a core/memory overheating issue ---> where the core/memory speeds are simply stepped down to the much safer 2D levels. And this situation is easily noted at the Rivatuner real-time Hardware monitor? However another possibility lies with the fact that the core volts regulator design of a 6800gt is not that good, and certainly not meant for running a core loaded at 430MHz. So I also suspect the core regulator chip may be overheating, and thus maybe being switched into a "amps" limiting mode? The Rivatuner Hardware monitor (via the VT1103.dll plugin) should also indicate if there could be a core regulator issue involved?
I have RivaTuner v2.0 RC16. I've used the monitor to see if there were any changes in core and mem clock speeds and they never changed. How do I use the VT1103.dll plugin? Is it already built in? Which graph is it? The "Core VID, non-dimensional" graph?
Try clocking the card back to 400 or so on the core. The problem was as described above. The card may be throttling under load. But another issue may be the PSU you are using. As most PSU's are advertised with their "peak" wattage. The problem is that your PSU cannot keep this up and when it starts to get hot, it loses efficiency and it's power output declines which will also be the reason for your under performing.
Definitely get a multimeter and check your volts on the 12V rail under load. Very very very first thing I would do.
I'm sitting here scratching my head wondering why you have the card UNDERCLOCKED at 430 mhz on the core when STOCK is 500 mhz?
Antec SmartPower2.0 350W ?? thats 25 amps across 12V ... Anyway .. i noticed the oc , and saw ur hynix modules doing ~23 MHs extra from stock .. i really doubt those modules can take such beating ... i can suggest one thing .. put ur CPU at stock and test .. i think the card is alright .. the problem lies elsewhere ... Even then .. if ur using stock cooling on the card , i'd suggest u to return to 420/1100 , the performance diff. will hardly be noticeable ...
After entering the Hardware monitor, select "Setup", then "Plugins", and then tick the "VT1103.dll" plugin to activate it ! Back at the Hardware monitoring display you should now see three new graphs, "Voltage regulator output", "Voltage regulator Temperature" and "Voltage regulator current" ?
lol, he must be thinking of the 6600GT. It does sound like QuanCannons card is throttling down due to heat. My 7800GS will do that also when overclocked to high even though there's no overheating of the core it's self. I think jimmor is correct.
i have had issues in the past when i overclocked my wifes 6800GT to far. i lost performance! like was suggested, run it at 400/1100 maybe for starters and see ?
LoL. Yeah, Estima8tor was right. It was late last night and I guess I didn't read well and assumed that "8" was a "6." SORRY! LoL
I think my PSU is an Antec SmartPower, not a 2.0 I've determined that it'll hold up when clocked to Ultra speeds (400/1100) because I was able to run 3DMark03 3x each test and still got something like 12.3k so I'll be doing more tests as I go higher up on the clocks. I'll wait for a really cold day and just leave the thing outside and do my tests, see if it is heat-related I've also upped the AGP voltage to 1.6V and upped the AGP clock speed to 70mhz (heard somewhere those changes will help stabilize the thing when you OC) FastWrite and SideBand-Addressing is disabled in BIOS, but for some reason SBA is on according to Rivatuner My main test is Battlefield 2142 demo, which seems to be pretty sensitive to overclocks (even at Ultra speeds I see occasional flickers) The card has a VF700 on it, and max temps are around 72C when running the ATI Tool stress test (it goes to about 68C max during actual games)
The need to increase Mobo AGP volts is usually associated with helping to improve the stability of an overclocked mobo/pci communications bus. In other words, when trying to improve mobo/agp bus communications bandwidth by increasing the AGP bus above the norm of 66Hz, it is generally also necessary to set the mobo AGP volts level above its norm of 1.5v. And, although arbitrarily increasing the AGP volts to 1.6v, or above, is unlikely to cause any harm, the same can't automatically also be said for increases in AGP bus speeds. For example, many mobo's have the PCI/AGP buses locked together, meaning that when one is increased so is the other. Unfortunately some pci devices, especially SATA HDD's, can become very unstable when operated outside a very narrow window around the pci 33Hz default. EDIT Also, your vga card is AGP 3.0 spec compliant. And as such, SBA is hard wired in. Which obviously means you shouldn't be too surprised that Rivatuner will show it as enabled !
