AMD64 3500+ stable OC, but visual errors in high-end games?

[ToniCrisolli]

Dear OC-frieds,

I was able to OC my 3500+ (Venice) to 250 Mhz and even much higher, and the system worked just fine, stable and cool (45C in full load) for more that 24h. All games, e.g. Quake 4, worked just fine and much faster. I have only one “small” but irritating problem one single game - TES4-Oblivion. The state of the art game Oblivion, a game that features HDR rendering and demands a strong CPU, is showing some kind of artifacts (polygons are jumping around and many textures are highly unstable) starting from 230+ Mhz FSB upwards.

Very similar problems normally do appear when over-OC-ing the GPU, but I did not even try to modify values of the GPU. I fixed the PCI-E-bus on 100 Mhz, manually. I also lowered the HTT to 3 and the CPU-multiplication to 10 (originally 11x200 Mhz). The Memory worked with 133 Mhz, instead of 200 Mhz, but still … no chance to get rid of these visual errors. This really frustrates me, as everything works fine.

Does anybody have a clue how to eliminate this problem when overclocking the CPU to 230+ Mhz? Is it maybe possible that the PCI-E is getting overclocked, even if I “fix” it to 100 MHz?

I would also be grateful for any advice and experiences from people having experience with this motherboard.

My system:
AMD64 (Venice, 2 stepping) 3500+@2200Mhz (air-cooled)
ASUS A8N-SLI Deluxe (latest official BIOS, no SLI-mode, all peripherals disabled)
Gigabyte 3D Cooler Ultra GT Edition (max speed)
Single Gigabyte 7800GT VIVO
2x512 Mb Kingston Value (works stable as a rock with 480 Mhz)
SB Audigy 4
Chieftec Big Tower 500W (8 fans)
750 Gb SATA
Windows XP SP2 32bit

Thanx in advance …

 

[harmonica]

maybe the extra heat from overclocking your cpu makes your gpu too warm. You could underclock your gpu and if you don't get artifacts anymore, I might be right. Or monitor your gpu's temperature while overclocking your cpu and while not overclocking your cpu, if you see a difference once again I might be right,


greetz

 

[ToniCrisolli]

Dear harmonica,
Dear all,

The GPU-temperature is not the problem, the clock-speed of the GPU and DDR3 also, unfortunately. The GPU is very well cooled and running cool, still, these visual errors do appear, even after I have just switched on the PC. In this case the system should be completely cool, but the errors do appear just from 230+ Mhz. I have the (hopefully wrong) impression that the PCI-E is getting over-clocked too, even if the bus-speed is “locked” at 100 Mhz by BIOS. It is not possible to lower the PCI-E-speed under 100Mhz.

The interesting thing is, in fact, that games, like Quake4, HL-2, Doom3 and others do not show such errors, at all, even if the CPU is running with much higher frequencies than 230+ Mhz and higher HTT values. Maybe, it is because the games do use an older shader model, but why should this be?

The system is in good shape. All drivers are up-to-date an all components are running cool.

Yet, I did not try to run games like Age of Empires 3, Fear and Splinter Cell 3. These games do use the shader model 3 and HDR, just like Oblivion does. I will try it out today and inform you tomorrow.

I would be thankful if everybody who is interested in these phenomena would participate with ideas and solutions. I am sure that this problem can be solved. It would be sad, if new high-end games could appear to be allergic to over-clocked platforms, because such games are actually THE REASON why we do over-clock our dear fellows …

Does anybody think that the motherboard is the problem?

Thx, good thinking …

 

[Thermalglow]

I had this exact same problem. All games worked fine except for Oblivion. I would get graphical errors and flashing polygons only while indoors. Had to clock my 7800gtx down to 480mhz. It was running at 490mhz. I did not change anything else and this did fix the problem.

 

[ToniCrisolli]

Thank you very much, Termalglow, I will give it a try this evening and inform you about the results tomorrow.

Does anybody have a clue why Oblivion does behave like that? Are there other games that react to OC like Oblivion? Is it a problem of the PCI-Bus, or something else (maybe the driver?)?

Thank you for being so active!