Gigabyte GTX 275 drivers

Playing Crysis on the weekend, the system rebooted unexpectedly. I
switched off the auto reboot to hopefully see what the issue was if it
happened again. It did happen again and it said a display driver had
failed but had recovered. Vista's issues and solutions thing found
drivers for the GTX275 and my monitor and I gave the nod to install
them. It happened again that night as I loaded a save game in Crysis. I
ran GPUZ and Hardware monitor so I could monitor temps and fired up
Crysis and loaded the saved game. As soon as the game loaded, it caused
Crysis to terminate. Temps were all in normal ranges for both GPU and
CPU. I redownloaded Physx software and it then allowed the save game to
load, mind you it was all stuck still, but I could move around.
Selecting restart mission seemed to rectify things and subsequent loads
from the new save point load without issue and temps according to GPUZ
and Hardware monitor are still fine. This morning when I switched the
comp on, it didn't boot. Just gave me a black screen. Hitting the reset
button and selecting start windows normally rendered a normal boot with
no further issues. I hope it boots fine tonight when I get home. Any
suggestions on this one?
Also, another annying ting I've noticed is almost everytime I open my
browser (IE8), it says the browser didn't close properly last time and
asks me whether to restore last session or go to home page. I select
home page and all is fine. Why would this be happening?
While I'm asking questions, anyone have an issue with CA Anti-virus
Plus reporting to Windows security that it is turned off? It appears to
be on and does it's auto updates and checks and stuff, but windows
security keeps reporting that it is off.
System is 3 weeks old approximately. Vista 64bit. i7 920 not
overclocked. 6GB ram. 2 x 500GB HDD's. GTX 275 896mb (Gigabyte). ASUS
P6T-SE motherboard.
Crash Lander

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