Random Blue Screens - I have tryed almost everything.

[inc123]

Computer:
A64 3000+ venice
S939 GA-K8N-SLI
Sparkle 7600GT 256MB/128bit PCI-E
WD 80GB JB IDE
2*512MB PC3200 400MHz CL 2.5 (dual)
Power color 400W
SyncMaster 740N 17" 8ms 600:1 1280x1024
Logitech MX310


I have had bluescreens since i got this computer. They are totaly random. Soetimes i gat BSOD (blue screen of death) 2-3 times a day. Sometimes I get one BSOD in a week. Sometimes i get it abter turning my pc on, sometimes after it has worked 8 hours. There isnt no diference what im doing - playing, surfing, using Photoshop i still get BSOD.

Things I have tried:
Multible format C:'s (reinstallin operating system)
Testing Memory with memtest - 36h testing and no errors.
I have changed my video from 6600gt to 7600gt.
I have changed my HDD from maxtor 160GB to WD 80GB.
I have changed drivers of my network card and video card.



Usually it gives the irql not less or equal error or sometimes pad pool header or then Page fault in nonpaged area without any file. If there is some file included, then mostly it is: nv4_disp.dll, NDIS.sys, mini.sys, nvata.sys


I need help badly! Any suggestions would be welcome.



BSOD's and error reports after them:

 

[diamond55]

even though mem test passed i would try new ram just to cancel it out..


all of them errors are caused by faulty hardware or newly installed software, also newly installed drivers..

if switching ram doesnt fix the issue maybe its a mobo problem

 

[inc123]

all of them errors are caused by faulty hardware or newly installed software, also newly installed drivers.

Basicly everything could be the problem...

Any more suggestions?

 

[diamond55]

have u tryed diff ram?