I know people hate wall of texts but theres gotta be a way to explain everything in detail
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Herms post pretty much sums up what to do in cases like this.
AVG has gotten pretty sophisticated over the past year and the processes that it uses can interfere in ways the avergage user wont understand. AVG is supposed to go in a dormant stage when you play games to minimize lag. I'm not sure if that feature is in the free version or if you have to buy the full version of AVG to benefit from it. I would suggest removing AVG completely, REBOOT and try your games a few times and see what happens. If you still lag, then AVG isnt your problem. Please do reinstall AVG or some other similar antivirus before you surf or download to prevent infection.
The above is true for firewalls too.... its best to completely uninstall them to remove the underlying process and test for lag.
As far as your ISP goes, yeah if you get lag while not using the internet then its probably not that, However you are still connected to a network which is constantly sending packets so its best to try rebooting any modems or routers you are connected too.
Sometimes I have run into situations where a monitor program for a printer will lag out a PC ... If the printer is turned off ... Its looking for the printer to talk to so keep your printers turned on.
The best programs I use for PC cleaning are used in this order.
1.) McAfee Stinger - kills running virus/trojan processes that may be running.
http://us.mcafee.com/virusInfo/default.asp?id=stinger
2.) Combofix .. I cant stress enough how valuable this program is. It will solve MANY problems with an ailing PC, Rootkits are very troublesome in todays PCs - let it install the recovery console if it asks.
http://www.bleepingcomputer.com/downloa ... s/combofix
3.) Malwarebytes Antimalware
http://www.malwarebytes.org/
4.) Superantispyware - this one will run on the taskbar after install but you can disable it
http://www.superantispyware.com/
Then finally - do a normal antivirus scan of your PC and defrag.
Reason I use #3 & #4 back to back is because they each have thier own detection schemes. So superantispyware will pick up bits left behind by Malwarebytes resulting in a clean thorough spyware scan of your machine.
Reseating your memory modules can help with preventing system errors. The heating and cooling of plug in components on a motherboard can make them work thier way out of a socket if they are not secured. Oxidation can contribute to poor contacts on the module. Simply remove the memory module and pop it back in, making sure it locks in place.
As far as antivirus goes - I use McAffe Enterprise 8.7i (One of the perks of working in IT at work, hehe)
but for being completely free, AVG may be youre best bet. Buying these antivirus pacakges will usually give you more functionality such as firewall and identity protection. Better support and more control over the programs.
Others out there with free trials are:
Kaspersky -
http://usa.kaspersky.com/
Trend Micro -
http://us.trendmicro.com/us/home/
Computer Associtates -
http://www.ca.com
and the well known Norton which in my opinion can make a pc run slow if you dont have the ram.
I hope this helps you and everyone else that may be having lag/computer issues.
. Now this happens offline as well AND it happens to me on some of the other games i play (Starcraft BW, minecraft...etc). Does anyone have any idea what could be causing this? I got this system in christmas of 09 and it never did it untill about a month ago. It started very slowly maybe once a week, then once a day, and now im getting it about 5 or 6 times a day (depending on how long i play). I must admit i have been lazy and havent cleaned the system once 
is it over heating? or is this some sort of driver issue? Am i just computer stupid? Dont think its my internet since it happens offline on other games as well......
