ouch, when you say "latest" det3's which are you talkin...official or beta's
If official, maybe they're not so good for vid board.
I am assuming that you have installed the latest via 4.25 4in1 drivers + the 4.03AGP driver...
go here for the drivers:
click me!
also, have you tried upgrading the bios on you card?
Some web site (I think its zohiah.org or something...) has complete descritions for doing this to most major boards. (plus he has alot of other goodies on there as well)
Also, check when you are rebooting your comp that the bios has recognized the ram amount correctly. I had a Hercules that had 16mb of RAM just up and die on me one day. I didnt even notice when I was booting that it was reading 16mb Geforce on the bios boot-up
Finally, run through the ABIT boards to see if other people have this problem. My A7V+Duron600@900+Asusv6800 are incredibly fast, but I ended up putting my geforce back in my P3 box since it is even faster hehe...