Having Lag/Choppy Gameplay: Click here

[[100]QuikShot]

This method worked for me:

1. Navigate to: My computer, C drive, Program Files x86, Steam, steamapps, common, call of duty black ops, players, click on config_mp (open in WordPad).

2. Find the line that says: seta r_multiGpu "1"

If you have SLI/Crossfire video cards, leave this at 1. If not, set to 0.

3. Find the line that says: seta r_multithreaded_device "0"

If you have a dual/quad core CPU, change this to 1.

So if you have SLI and quad core like me yours would look like:
seta r_multiGpu "1"
seta r_multithreaded_device "1"

4. Save and close file.

5. Load Black ops and click Settings, then Graphics. Where it says Sync every frame, change to NO.

Post if it helped or not. It did for me.

Quik

[Syzygy]

Current Specs
Processor: Intel Core 2 Quad @ 2.83GHz Q9550 Yorkfield 45nm Socket 775 LGA (65W TDP)
Overclocking: 3.6GHz / 2.7GHz throttled
Mainboard: ASUSTeK P5E Deluxe (Intel x48)
Memory: G.Skill 4GB (2GB x 2) DDR2 PC2-6400 Dual-Channel (5-5-5-15)
Storage: 1x 1TB Western Digital Caviar Black, 1x 320GB Western Digital Caviar Blue
Graphics: 1x nVidia GeForce 8400 GS (512MB)
Display: 2x Sceptre X20WG-Naga Black 20.1" 5ms (1680x1050 each)
Operating System: Windows 7 Professional x86-64 (64-bit) v6.01.7600
Mouse: Logitech MX1000 Laser (Not a gaming mouse)
Keyboard: Logitech Media Wireless Keyboard (More latency than I'd like)

I went through with the .cfg mod and have noticed a slight increase in performance. I still have issues with Jungle (18~22 fps avg). Best performance I can get is Firing Range (27~30 fps avg).

Future upgrades
Video Card: EVGA 01G-P3-1366-TR GeForce GTX 460 SE (Fermi) 1GB 256-bit GDDR5 PCI Express 2.0 x16
Mouse: Logitech G700 Gaming Mouse

[[100]QuikShot]

syzygy your 8400gs is definitely the problem thats holding you back. Once you upgrade your video card, you should have fps in the 80s, 90s or more. The rest of your system looks like it should be able to handle black ops just fine.

Quik