Vista - unable to run 8800 gts in sli

I have tried to run sli configuration for days and it will not load, when get through with the post before the load screen comes up...the dreaded BSOD, and it reboots. the blue screen is so short I'm unable to capture or read any of the messages. when I go into bios and only set to run 1 card no problem, yet with 2 it will not run.... I'm running dual boot system (separate drives) and with xp no problems at all. currently running 169.21 drivers, have also tried 174.74 same results, I have installed sp1 and didn't help the issue
I want to run this set-up, yet can not get it to function.... YET....
Any and all help is greatly appreciated, thanks in advance...

not positive, haven't run any good bench's yet , but I believe I've gotten it fixed disabled cache and reinstalled new drivers.... so far seems to work.