UT3 : Application error on Vista x64

Hello all !

I have a little problem with UT3 on Vista x64. Sometimes i have this
message :

-"UT3.exe - Application error.

unknown software exception (0xc0000005) occurred in the application to
the location 0x0076480b"-
Then, I press OK and the game close. I got this message once hellgate
london too...

My drivers are up to date, windowsupdate = ok and the game is also up
to date. My pc is ok too (memtest = ok, hard drive disk = ok etc.)

Then, is this vista or UT3 ? Any ideas ? Come back on XP and drop Vista
? ...

NB: I'am french, it's possible that my English is not "OK"

My PC :

Asus P5KC
C2D E6750 @ Stock
2 x 1Go DDR2 PC6400
Crossfire HD3870 with Catalyst 8.3
1 x HDD 250Go
Corsair HX520w

Thanks a lot !


--
eRoKz