I am getting a new case that has 4 80mm fans, and im getting a new mobo and new faster 2.8 GHz processor. so should i upgrade or keep my 200 watt stock psu???
yep i would get a PSU around 400W, most mid range gaming comps right now run happily off about 300W (my sig rig uses about 290W but i have a Antec Neopower 480W) but the bit of overhead is nice so that your can upgrade
I would really recommend a Tagan 380W, really solid build quality, using one now. TBH, electronics is the wrong part of the forum.
If you are going to get a new PSU make sure you buy a good one as a poor one can only cause more problems. For a 2.8 you shouldnt need anything more powerful than a 350W but just make sure its good and you should have no problems.
A decent brand being Enermax, Tagan, Antec, PC Power and Cooling, Silverstone, and SeaSonic (I have experience with all but Tagan).
Anything quality of 300W or so will be fine. Good manufacturers are Tagan, Zippy, Fortron, PC Power and Cooling, Seasonic, Silverstone and Antec.