Bottlenecking GTX 260/216?

[UNnamed66]

Hi, I've recently upgraded my gpu to EVGA GTX 260 Core 216 Superclocked Edition to play GTA IV. But my FPS is around 12-20 in city where other GTX 260/216 users have more than 40fps. My GTA IV graphics settings: Texture Quality: Medium, Reflection Resolution: High, Water Quality: High, Shadow Quality: High, and Texture Filter Quality: High. Only 430+/896 MB usage. GTA IV update 1.3.0 installed. Is this normal or one of my specs is bottlenecking. And my CPU is over 55C+ with no overclocking. My guess it's the mobo tat is bottlenecking?

My Specs:
Intel Core 2 Quad Q6600 Kentsfield 2.4GHz
XIGMATEK HDT-S1283 120mm Rifle CPU Cooler
EVGA GTX 260 Core 216 Superclocked Edition
Antec P180 Case
ASUS P5N-E SLI LGA 775 NVIDIA nForce 650i SLI ATX Intel Motherboard
OCZ GameXStream OCZ700GXSSLI 700W
Seagate Barracuda 7200.12 ST31000528AS 1TB
CORSAIR 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400)
Windows 7 RC x64

 

[MMclachlan]

Overclock your quad! I run Q9550 @ 3.5Ghz with 4Gb RAM at 825Mhz 4-4-4-12 and 8800GT SLi @ 1920x1080 with medium textures and everything else high or highest and get minimum of 20-25fps in the city in the dark and rain, otherwise usually about 40-45.
Make sure you have the lastest drivers installed.
Also, you might as well push your grahpics settings up to make use of your available VRAM. Its a waste otherwise!

 

[Amg]

give that quad a kick in the butt (overclock it )

not sure how the 6 SLI chipset overclocks I would say you should get 3.2Ghz out

I have a Q9550 on a X48 runinig at 3.8Ghz

 

[Gin Fushicho]

You need to overclock your quad to at least 2.8Ghz , and yes I believe your MOBO has a possibility of bottle necking it.

http://www.nvidia.com/object/motherboards_buy_now.html