My pc had 2.8ghz processor and 3gb ram but still super slow!

[joey 22]

hello, i dont know much about pc but the little that i know might be enough. i had a pc that had an intel (R) celeron (r) 2.8 ghz,
3gb of ram,
64gb hdd - one 40gb and other 20 gb,
via pm 9400 motherboard

thats all i knw about it. it stopped working a few months ago and now doesnt start at all.
1. it was very very slow in using almost everything. just want to know if the processor was really that slow.
2. i checked the powersupply to motherboard connection if something made it go wrong adn found that the atx connector to motherboard(two black wires and two yellow wires) made it stop work, but when i turn on the pc without these wres it started but nothing came on the screen.

 

[joey 22]

ok tanx, i jst needed some clarification. its fried now so i wont even bother gething it fixed now. sell the used parts nd get a newewewewer one. the only thing that made it work faster was when i played music on winamp. dont ask how or why... it just did.