system freezes and monitor doesn't start

[callmeastha]

hey guys sometimes(not always) when i switch on the mains supply of my pc the monitor light glows green and then goes orange but on switching on the cpu it doesn't turn back to green and the monitor doesn't start though the cpu starts and keeps running fine...if i keep switching it on and off repeatedly eventually it does start up

also very often after starting up and after varying intervals of time my pc just freezes all of a sudden(and if any songs are playing they don't get stuck but stop playing)then all i'm left to do is switch off from mains and restart...ctrl+alt+del or win+l or win+m nothing helps...and it happens quite often...whay does it happen and what do i do?

i use win XP professional with sp2 512MB RAM pentium 4
C:total size:8.79GB free:1.67GB
D:total size:9.84GB free:1.22GB

thnx

 

[nvidia]

See if your monitor is correctly connected to your motherboard/graphics card.

 

[brokenheart]

hey dude...plz chk ur ram in their slots......
jus reinsert them....by cleaning the ram-slot.....
also do check ur power cable conn with the harddrive....

 

[callmeastha]

checked all the wiring and reinserted ram...to no avail