Taken from the Steam forums.
Summary of game optimizations and analysis of some trends. Updated with 12/15/10 patch info now. Be aware some optimizations work for some people and some don't.
*** Game version is 7.0.42 after patch released 12/15/10. Bring down the game console and you should see that number.
Most with Intel Core 2 Duo's are saying the game runs much better now.
Most with AMD dual cores are saying their issues are still there.
A lot of people who still have issues believe it is related to sounds, particularly RealTec Audio.
Most are saying it runs much better on Windows 7 now than it did prior to patch.
Some are saying that enabling new option Shader Warming makes the game run worse for only the first game or so but then after restarting the game again and playing with that option on that things run better than before patch.
*** Stutter: Seems like most people who have resolved issues with game stutter are finding the solution by adjusting their sound device KHz value in Windows to match what their multiplayer config file says the value is for "seta snd_khz", or deleting their config files after backing them up and letting the game rebuild them.
*** Game files up-to-date (Steam check):
In Steam/Library/right-click Call of Duty: Black Ops/Properties/Local Files/Verify Integrity of Game Cache.
Do that for the single player & multiplayer both (even if you don't do the single player) then restart Steam completely.
*** Game files defragmented (Steam check):
After a while of heavy gameplay the game files can get fragmented and some stutter can start to occur because it. They need defragging so you can get back to fragging.
In Steam/Library/right-click Call of Duty: Black Ops/Properties/LocalFiles/Defragment Cache Files.
Do that for the single player & multiplayer both (even if you don't do the single player) then restart Steam completely.
*** Steam options:
In Steam options select "go offline" to reduce any system overhead due to Steam working in the background during your game.
*** Graphics in-game:
Increase (rather than decrease, oddly enough) Texture Quality, Anistropic, and Anti-Aliasing, for better gameplay. Theories for why this works is that it seems to take some load off of the CPU or differently regulates the way data is sent/received to/from the server.
Turn off Shadows for increased performance. Noticably so for this game.
*** Graphics in Windows:
Right-click BlackOpsMP.exe and in the Compatibility Tab put a check mark for 'Disable visual themes' and 'Disable desktop composition'
*** Graphics with certain video cards:
NVidia: It's possible that setting to High Quality in NVidia Control Panel improves gameplay.
NVidia driver 263.00 working good for all cards.
NVidia driver 265.90 working good for all cards if you get the international version then use a modified inf file to make it work for all cards.
ATI: Some are saying that stopping Catalyst Control Center in the background improves gameplay and they're recommending latest beta driver.
*** Sound:
* 1) Check your config_mp.cfg, find the setting "seta snd_khz" and see what the value is, leave value there, go into Windows Control Panel and make sure your PC's default device matches this. Change to match if necessary.
This fix only works with Win 7 & Vista due to the way the sound stack works.
For those using XP set your PC's hardware acceleration to the next-to-lowest position on the slider (not the very lowest because that makes PC not use Direct Sound) then reboot PC then run XP's Sound Hardware Test wizard so Windows can adjust itself for it.
* 2) Try out disabling your PC's sound device, rebooting, then trying the game again to see if your game issue goes away when it's like this. Not a good permanent solution in itself of course but if the test proves positive then try one of the other things on this list.
* 3) Get add-in soundcard, preferably a PCI-express model (particularly rather than using motherboard sound)
* 4) Get a USB headset (particularly rather than using motherboard sound)
* 5) Set snd_losOcclusion to "0" and set snd_enableEq to "0" in config file.
* 6) Type /snd_restart in game console while in the game and press Enter.
*** Config file Tweaks:
Before you modify your config_mp.cfg file copy it to My Documents for backup.
It's probably at one of these two locations:
C:\Program Files\Steam\steamapps\common\call of duty black ops\players\config_mp.cfg
C:\Program Files (x86)\Steam\steamapps\common\call of duty black ops\players\config_mp.cfg
Right click on it and go to Open With... Select wordpad (not notepad).
* 1) r_multiGpu "0"
Should be a 1 if you have multiple GPU's and should be a 0 if you don't. Adjust it if it is incorrect.
* 2) r_multiThreadedDevice "1"
Theoretically this should be a 1 if you have a dual core or quad core CPU and should be a 0 if your CPU is single core only.
However some people with a dual or quad core find it's better for them to set it to a 0. You can experiment.
* 3) seta sm_enable "0" - this value disables shadows, boosts performance
* 4) seta r_blur_allowed "0"- this value disables visual blurring effect, boosts performance
* 5) seta r_motionblur_enable "0" - this value disables visual blurring effect, boosts performance
* 6) seta cl_maxpackets "100" - Adjust it for this value.
* 7) seta cl_packetdup "5"
Actually best value to set depends on your ping to the server you're playing on.
Ping 20 set 1, ping 40 set 2, ping 60 set 3, ping 80 set 4, ping 100 and up set 5.
*
Some people report that after deleting their config_mp.cfg file then going back into the game it creates a new config_mp.cfg file and their game runs much better. Be sure to back up your original one first just in case.
*** Reducing Game Priority in Windows Task Manager:
Some say that if they go into Windows Task Manager/Processes/right-click the game on the list and change Priority to Below Normal or Low it makes it run better, presumably because the game was programmed to use too much CPU resources.
*** Overclocking CPU:
Overclocking CPU on this game has much more profound effect on game smoothness than it does on other games but will not resolve issues such as stutter or freeze in itself.
*** Operating System:
* 1) Some people are saying switching from Windows 7 to Windows XP fixed everything for them, but many say it's running fine on Windows 7.
* 2) Some people using Win 7 or Vista are saying that running the game in Compatibility Mode for Windows XP makes the game run much better.
* 3) Turning off SuperFetch service and Indexing may improve gameplay.
* 4) Manually setting your Max and Min Virtual Memory to the Recommended Value may improve gameplay.
*** Third-Party Utilities:
Some people are saying their gameplay has been made better by using third-parties tools like Game Booster which shuts down unnecessary system processes in order to improve the performance of resource-thirsty game.