Help for MSI 790FX-70GD & Sapphire 4890 Toxic Problem

[kokin]

So I have a Sapphire 4890 Toxic and I'm using ATI driver 10.1 (problem occurs with older drivers if I revert back), as well as a Phenom II x4 955 and a MSI 790FX-70GD (1.8 BIOS). I've noticed that my FPS have dropped a little and I can't seem to OC as high as I used to (previously 1050/1140, now I'm barely stable at 985/1100). My Vantage scores have dropped from 12-13k(stock-OCed) down to 10k(stock and OCed) and I don't know what's wrong. I did notice that during idle, CPU-Z/GPU-Z/Everest read that I'm at PCI-E 2x v1.1 speed, while during load, I'm at PCI-E 2x v2.0 speed. My motherboard supports 16x/16x/8x/8x and both PCI-E 16x slots report the same thing. Am I facing a problem here or what?

 

[kokin]

Well after a few days of searching, I found out that reseating the GPU reverted it back to it's 16x speed.

 

[mrcmark]

people reported dropped scores in the new 10.1 catalyst driver. you can go back to 9.12

 

[kokin]

Hmm, well I can OC back up to 1050/1130 on stock voltages now, but my Vantage score is still at 10.2k regardless of stock or OCed clocks. I'm probably being limited by Win7. I remember there was a recent article in THG that mentioned lower 2D performance with Win7. Having previously used Win7 RC, my scores would be 12k @ stock and 13k OCed, but ever since I've installed Win7 Professional during December, my scores have been rather low.

EDIT: Btw, I've tried using 9.7,9.9,9.12, and 10.1 drivers and I'm still stuck at 10k.