Windows Vista (problem also existed on XP). Problem also occurs regardless of CPU overclock.
Note: System is prime stable and memory testing reveals no errors. CPU, at full load, hovers around 43-44 degrees. Cooling and airflow are excellent.
I have been experiencing artifacting after several minutes of gameplay. The artifacting can be best described as spiking--textures out of place. This type of artifacting is commonly associated with video memory corruption. I would like to confirm that this is in fact the problem so I would like some opinions. I have discovered that the problem does not occur unless the GPU reads above 60C. If it gets hotter than that, it usually starts artifacting around 62C and gets worse at 64C. If I alt tab out, let it cool for a minute, and then go back into my game, the artifacting reoccurs when the GPU again is heated up past 60C. Also note that the card voltage regulator usually reads about 4 degrees higher than the GPU.
In ATITOOL, I set fan control to 100% override to ensure fan speed was not a factor. I also added a fan card under the GPU. I ran prime95 and scanned for artifacts at the same time. When the GPU heated up past 60C, it did not detect artifacts but I could see a few yellow dots appear on the cube.
Underclocking the video memory seems to have no effect. When temps exceed 60C, the problem reoccurs.
No display corruption occurs in the operating system. I am running Vista premium and so the operating system is using the graphics card, however, in normal applications video card temperature is more like 52 degrees. Only in games and stress tests does the card manifest problems.
My question is, given that I seem to have linked the problem to card temperature (1) could other components be part of problem, like the mobo or powersupply (2) what other settings/tests can I adjust to try and eliminate the problem (3) what conclusions can I draw from the fact that the artifacting occurs around 60C? It seems to me, the X1800XT should not be malfunctioning at this temperature.
I also had a Sapphire X1800XT 256MB card go bad on me earlier this year. My symptoms were similar to your's and no amount of playing around with drivers, cooling, seating/reseating, etc. would make the "spiking" go away. I deduced that the memory probably crapped out, which sadly seems more and more common amongst these cards. I ended up RMAing my card to Newegg and got it back in a little over a week and have since not had any problems with it. That's probably your best bet at this point.
Best of luck to you. I know how bad it sucks to not have a functioning card in your system for a while, but it'll be worth it in the end.
Normally that is a driver issue if the board is not damaged -roll back drivers - or use original drivers.
as a psu gets hotter the efficiency drops so does the output - but this does not seem like a power problem.
or send back to ati for repair - 1 yr warranty
uninstall all cat/ati software - disable drivers (you need to reboot if you loose your monitor) disable auto driver loading in windows (found new hardware)
reinstall original software that came with card - let cat install drives.
check for problem - if problem occurs send to ati
no problem try new cat drivers - if problem occurs do roll back
search for older drivers and repeat above
note: i run x1950 full oc 695/700 1098/1100 in overdrive stock cat software. air cooled. I have fans that blow air at the cards from the front. I have a hole in the case next to the cards with foam as a filter. The cards need good air flow - idle is 68c and 78-80c in the oc utility. if you at 95c + plus your going to melt the epoxy/packaging. I really think you need to keep these card below 85c.