Wheelman frame drop Gigabyte GTX 260 SOC

[revo]

PC Specs:

CPU: Intel i5-750
MOBO: Gigabyte P55A-UD3R
RAM:Team Group Elite DDR3 4 GB 1333 Mhz
GPU: Gigabyte GTX260 Super Overclock GV-N26SO-896I
HDD: Samsung 500 GB 16 Mb buffer SATA2
OS: Windows 7 Ultimate x64
PSU: GIGABYTE GE-P450P-C2
FANS: 2x12 CM + 1x90
OTHER: 1 TV Tunner

Driver Version: 196.21, also tried the latest beta driver from nvidia website

In wheelman on a 1280x1024 resolution my fps are between 90-120. The thing is when I drive a car from time to time I get a suddenly frame drop to 10-20 fps which lasts about 1-2 seconds and it's really annoying. This thing happens in other severall games like GTA IV as well (which I know is bad ported, but anyways... why?). Metro 2033 is running flawlessly.

Temperatures in full load:
Processor: 35-50
Mobo: 35-50
Video card: 50-70 (with fan at 60% speed)

Any suggestions? 

[j2o]

hi raceing games are the most demanding

as an nvdia guy GTX series just dont cut it (128 bit float) , my old 9600GToc is more power full by far(256 bit) .even better myGTS 250 1gb 

driver should be 197.45 for vista 64bit

[pcb-plus]

hi have you checked to see what other software or windows services you have running that might cause the issue
windows 7 uses the gpu more than any other o/s so it may be software or a service in the background giving you the trouble
what are you using to monitor fps and have you tried to play the game without monitoring the fps sometimes things like frapps cause issues like this I have had one game unplayable with frapps running but turn it off and the game runs fine ( problem was cured with new release of frappsI might add

I may be way off the mark but worth a look