Games slow after rebuild

[clok555]

alright so i took apart my computer to use the parts in another case. upon realising it wil be days before my new system will be ready i decided to put my parts back in. (dimension 9150) so i boot up the computer everything works. thank god. but games (burnout paradise) run slower now. ok so heres what happens: every 10-15 second the frame rate drops to unplayable like 4 fps. i normally play around 15-20 cuz im used to it XD but this frame rate drop often causes me to crash my car. now im assuming that maybe the card has to clear the RAM or something every ten seconds but it never used to do this. i have the same amount of RAM same cpu same video card i even tried improving cooling but my card is perfectly cool. software changes: i installed a printer. i have tried going through my startup programs but no improvment on this problem. so if anyone has an answer please help if you need any more info just ask.

my specs

amd radeon hd 5450
pentium 4 2.7 ghz
1.5 gb RAM

 

[xunicronx]

When you installed the printer, did you happen to install software with it too? Some of the software could be active in the background while you are gaming.

 

[clok555]

i didnt see any HP services in msconfig. i was hoping it would be some silly hardware mistake

 

[erikalikesfire]

Did you clean the old thermal compound off the cpu and apply new compound when you put it back together? Try installing openhardwaremonitor or coretemp or something and see how your temps are doing when running games. If that processor is the E5400, the max temperature is 74.1º C. http://ark.intel.com/products/40478/Intel-Pentium-Processor-E5400-(2M-Cache-2_70-GHz-800-MHz-FSB)