Anyone else getting an odd jitter in the graphics as your driving

My Specs are

Processor: Intel Core 2 Quad Q8300 2.5Ghz @ 3.10Ghz
CPU Cooling: Nexus XiR-2300
Memory: 8GB Kingston DDR2 PC6400
Hard Drives: 1.5Tb Seagate 7200.11, 500Gb Hitachi P7K500, 320Gb Samsung T166 & 200Gb Samsung SP2004C (2.52Tb Total)
DVD Drive: Samsung SH-S223Q
Video Card: ATi Radeon HD 4870 512MB (790/1100)
Gfx Card Cooling: Zalman VF-1000
Monitor: BenQ V2210 Eco 1920x1080 @60hz Connected Via HDMI (Full 1080p HD)
Sound Card: Creative SB X-Fi Xtreme Gamer
Network: Realtek RTL8168C
Capture Card: Hauppauge WinTV-HVR-1100
Speakers/Headphones: Creative Inspire A200 2.1
Keyboard: Microsoft Comfort Curve 2000
Mouse: Logitech MX518
Mouse Surface: WoW Wrath of the Lich King SteelSeries QcK Gaming mousepad
Operating System: Windows 7 Ultimate x64
Motherboard: Gigabyte GA-P43-ES3G
Power Supply: Corsair HX 750W
Computer Case: Cooler Master: SM Storm Scout

Thanks in advance

What do you mean by jitter? I do get opponent cars and certain objects flickering in and out. I've tried several settings but no luck so far...

W7/64 / Nvidia

i dunno best way to describe it is like every 3 or so frames it seems to lock up for 1