Hello to everyone.Yesterday I took a tower from a friend of mine because sometimes when he pushed POWER button,the computer wouldn't start and sometimes was starting.So I decided to open it,clean it,get rid of all un-necessary hardware and to fix it.(Sorry for my english...yeah yeah I know). I unplugged all hardware,cleaned the tower from the dust and I plugged them again.The system is: MSI K8N Neo4 - AMD Athlon 64bit - 512MB RAM DDR400
SAPPHIRE ATI X550 256MB PCIE
PSU 500W - MAXTOR 120GB IDE - DVDRW NEC
So,when I checked everything that it was plugged correctly I pushed the POWER button.Now pay attention...All the parts started,fans,HDD,DVD,but I didn't get that SINGLE BEEP sound!!! And the monitor was always in STANDBY!!!
Why is this thing happens??? I have repaired over 80 PC'S in my life and I first met that problem in July 2009.
Well,I thought a few things:
01. I tried another 2 PSU's (300W & 400W).
02. Tried with another PCI-E graphics card.
03. I've disconnected all un-necessary hardware (FLOPPY-HDD-DVD + USB cables inside + RESET button)...still nothing...
04. Put MOTHERBOARD out of the case only with CPU & CPU FAN
05. Checked RAM by using 4 different DIMM's in every one separately DIMM SOCKET
06. Changed the PSU power cable
07. Changed the MONITOR cable
08. Checked the JUMPERS to see if they were in the correct position as the manual says
09. Plugged the tower in another room
10. I unplug the PSU cable and pressed the POWER button to dis-charge the capacitors
11. Changed the SPEAKER & the POWER button
12. Took a multi-meter to see if the motherboard gives 5V to SPEAKER
13. Changed the CPU fan
14. Tried to BOOT without the RAM
The crazy thing he said my friend is that sometimes it was booting normally to windows!!!!!!!!
So am I getting crazy??? After 10 hours of checking I have lost my patience...
PLEASE HELP ME!!! Your comments will be very useful,thanxxxx!!!