Causes of lag ?

usually when i search for causes of lag , it's always that the hardware isnt good enough to support the software or game or virus or so that's causing the lag.

however , what could cause an overnight lag ?

as in you were able to play this same games for years without prob and all of a sudden your com suddenly lagged when you play the same game.

lets assume your com laggginess is not cause by viruses cause thats what happen to me com .

i've scan with known reliable antivirus and antispyware such as NOD32 , avg 7.5 , kaspersky , ad aware , spyware terminator , spyware doctor ..

yes , some require payment but i scan and my com is clean.

Causes of lag ?free antivirus

Try checking out your Video Card drivers, if they're using the default Windows provided drivers, change them immediately, they're pretty slow, not configurable and doesn't support OpenGL as well.

Check your RAM, some of your RAM might have come loose resulting in reduced usable RAM, which could slow your game down. (Happens to be at times.)

Try to disable Speedstep or Cool n Quiet. They slow the processor down, but they could prevent overheating processors, which makes it to this point.

Check your fans, some of your fans might be dead or clogged, causing your processor to slow down in order to compensate on the heat.

Causes of lag ?internet

Try ctrl-alt-del to call out windows task manager and view procesess runing on back ground, should give you a good idea of what causes the slow down. Stop process that eating up the memory, delete if necessary.
have you checked your disk space in your hard drive? and also your memory storage space? there are tendency that compter may log when this will down in capacity...

hw bwt your memory? hw much space would it be right nw? you disk drive is ok...the partition usually doesn't affect it...