8800 GT Vs. 9800 GTX+

Grettings.

Im in need of assistance, i recently bought a Zotac 9800 GTX+ CUDA to replace my Zotac 8800 GT... which was a mistake in my eyes. The problem is, my 8800 card has way better frame rates in the games im currently playing (WAR, WoW, Fallout 3 ect.) and i have no idea why, i benchmarked em both in 3DMark Vantage and the numbers was pretty different:

3DMARK Vantage Test.

Resolution:

(1280 x 1024)

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Zotac 9800 GTX+
GPU Score: 6621
CPU Score: 6588

Total Score: 6613

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Zotac 8800 GT
GPU Score:5715
CPU Score:6730

Total Score: 5939


9800 GTX (recorded with fraps)
(Res: 1600 x 1080)

Average frame rate in the bellow listed games:

WAR: 23-26 fps
WoW: 75-95 fps
Fallout 3: 29-33 fps

8800 GT

WAR: 56-66 fps
WoW: 81-99 fps
Fallout 3: 40-49 fps

I tryed to slap em in SLI but it didnt work, the SLI expansion slots are slightly off so the SLI bridge that has to be connected dosnt fit.

Anyways, on papir the 9800 GTX should beat the 8800 GT, im at the point i just wanna "snap" an slap in the 8800 GT again unless some of you guys can pinpoint the problem. I even fiddlet around in the Invidia Control Panel switching stuff on/off but no luck.

Thank you for your time!