Help! My Dell Laptop Has A Problem

Guys, i need a lasting solution to this. My DELL INSPIRON E1505 laptop has a big problem. I'm operating on win xp and the laptop uses a dual core processor with 1.6 ghz. The ram is one gig and everything has been running smoothly till last month. I used to be able to play games like PES 09 and others on it and everything was working fine.
Last month i noticed the laptop was beginning to run slower and hung on several occasions.
I recently posted a topic concerning it and was told to format it or use another OS.
I formatted and reinstalled the win xp but the problem is still persisting. Sometimes when i check the speed, it displays 5.3 ghz or even speeds like 38.5 ghz instead of 1.6 ghz. Please i need to know if the processor has a problem or what the problem is so i can fix it as soon as possible.
Please i need your answers and nobody should suggest getting other Operating systems unless they can run nice games.

Ah i rmbr u, n i dont rmbr telling u to get anor os!
Hmmn, now dt u and your advisers have succeeded in foolin urselves, maybe u shld go back 2 that thread n read carefully, cos quite clearly u didnt 4llow d reasonable tips given 2u dere. U pple jst always blive formatting cures all like beheading cures headaches.


Suffice 2 say, u are about 2 hav hardware failure, hopefully just 1.
I dunno if dell bios has diagnostic tools, if it has, use it. Or else u could use external ones.

Personally i thinj its your hard drive or ram or both. But of course u need 2 diagnose. I rmbr tellin u dt u be prepared 2 buy a new hard drive! Processor no dey spoil like dt n even at dt it wont be a gradual thing. But right now d stress u givin it 2 compensate 4 d oda bad parts is killin it.

Anyway, d advice is free, so your on your own!

@ 4llerbuntu
chill man, i didn't mean any insult to anyone with the os comment. I was trying to notify anyone who might suggest it that gaming was the priority.
I went to comp village on friday to get a new one but my dad was in a hurry and i had go for my lectures at unilag. I discovered the one the seller was trying to give me did not have nvidia or ATI radeon video card. So i decided to wait till next week.
I'll try adding linux to the new pc. Hope this wont cause problems on win 7.
PS: I tried some of the solutions before formatting. It still didn't work and that was why i formatted it. I'll make sure i take care of the new one better,  Does anyone know where i can get Gears of war for pc?