Bad Memory=BSOD?

I have a Prostar 5600D with:
celeron CPU 2.40GHz
256 Ram
ATI Mobility Radeon 7500
40GB HDD
8x DVD/CDRW

lately, it's been shuting down with the BSOD after a few minutes use.
The BSOD messages i get are:
bad pooler
page error
irql not less or equal
ntfs.sys
win2k.sys...etc

anyone got any clues...the kid i got it from said he'd overclocked it before and
tried to change the memory

 

Its overclocked and is unstable.....

 

the guy oced his laptop? Hm.. definatly gotta be that... laptops dont usually stay stable at oced speeds. ACE 256 can help you if u need to "under"clock it

 

well, i need help in all aspects of fixing the darn thing...
this is my system...
http://www.pro-star.com/index.cfm?mainpage=productdetail&model=5654

please help...anyone!

 

That cannot be your system because it shows a pentium 4 at 2.8GHz. Maybe you gave wrong link?

 

it's my system with the proper upgrades...as i said the kid i bought it from changed some things...

mine has 2.4GHz, 256 ram, and Radeon 7500...everything else is correct as is on the link

 

going to need more than just that...thanx, i tried it and still have probs

 

A CMOS clear should do it inless he took a soldering iron to it or something ...

 

not very computer savvy....what's CMOS?

 

unable to find the cmos battery...tried some other solutions and finally got my laptop to stay on (stayed on and working for about 1 hour). i loaded all my drivers and restarted the laptop. after about 15min. i got a BSOD about the physical memory dump...

any new suggestions?

 

http://www.majorgeeks.com/Memtest86_d4226.html

Run it for several hours.