Why does the PS3 lag so much?

It started happening about 3 months ago. It was perfect I never had any lag whatsoever but now I can't even finish a game in Battlefield 3 or any Call of Duty because I end up lagging out, heck, even LittleBigPlanet 2 lags like crazy when I play it....

So for 2 years I've played on my PC which was a very powerful rig ! But recently last week, I bought a PS3 Slim & I've been noticing some lag (basically rendering lag,) on most games like KZ2 (appears to run in about 35 to 40 fps & not 60), Fallout...

I have two ps3's and everything was fine until a couple days ago... I was able to play online without any problems even when My brother was using the other ps3.. But recently when I play cod black ops and my brother turns on the other ps3 it starts to...

I know the ps3 has internet lag ' if host is bad ' or etc..... but it doesnt lag in FPS like foreal my ps3 is from 2008 Gets over 50FPS on mw3? And my computer is from 2011 and gets 100Fps but then when i hit Fraps on boom drops to 25FPS... -_-

It suddenly started happening just a few minutes ago. My ps3 slim freezes when I put in a movie and play it. It goes black and I would have to hold the power button for 10+ seconds for it to turn off. Then at startup, it freezes before I could log in...

Ok, had my PS3 for a while and had a bluetooth head set for 3 months now. I play COD online and i use my mic everytime I play. I have had no problems at all for three months. Suddenly yesturday when i play online and turn my mic on I get really bad lag...

At hOme it's normal but at my dads house my ps3 takes a while to register what my controller did like I turn and it turns after a small delay...it's annoying for cod...why is it lagging only at my dads house

Is there a way u can use multiple connections without having it to slow down and lag

i think it started when i updated to 4.00. it doesnt overheat (especially with the modded fan) and its a 160 gig slim. is there a defect in the 4.00 update or what?