I think your right, I tried it all at stock, I clocked it down to 2.66 and 2.8 and it used to run perfect everytime on that, everytime.
I tried the RAM all at different timings and still everytime I get the same now, games are fine and everything else is fine, its just ever since i tried to clock my graphics card since the first time I unlocked it, I've had nothing but problems and artifacts and so on, but only in 3DMarks2005 and 2006 and mainly on the forest scenes, sometimes now it won't even run the full proxycon scene where as before it did everytime, I have tried numerous voltages and settings and still the same.
I've formatted, reinstalled drivers and tried different versions, I think I may have damaged my graphics card trying to clock to high the first time, I just raised the mem and the gpu right up and expected it to work, very nieve I guess.
I knew I should have left it alone, any ideas on what to do now? or is that a stupid question?

Or could it be something to do with the RAM? can that cause problems like this?
Basically gets to the same scenes everytime, it starts to become unstable and usually locks up or artifacts first then locks up totally. It does not usually go blank it just freezes totally, but you see it becoming unstable sometimes before it does, not all the time though.
Here are the results when it actually used to running at 3.22Ghz and 920Mhz 5-5-5-15.
3DMark Score 5511 3DMarks
SM 2.0 Score 2008 Marks
SM 3.0 Score 2234 Marks
CPU Score 2836 Marks
But I have It running at 3.325Ghz and 950Mhz 5-5-5-15.
Can't bench it because it crashs regardless if I default everything in the bios or not, running stable on Orthos though.
At the settings above, It ran and I changed my PCI Freq from 100 to AUTO and my Mipmap detail to high performance, this was ran on the 7.1s, but I am going to try again on the 7.4s as the score looks poor, however at least the CPU works lol.
3DMark Score 5490 3DMarks
SM 2.0 Score 1985 Marks
SM 3.0 Score 2221 Marks
CPU Score 2930 Marks
Well tried to run it again and it crashed in the forest typical.