Ok, I've installed everything.. I get the Bios up and running.. everything seems to be working.. it recognizes the memory and the Hard Drive.. I even managed to get inside the Temperature settings and see that the CPU works at a cool 26-27 C , and then, BAM.. 30-40 seconds later.. screen shuts off... and I can't even turn off the computer from the button at the front.. just by turning off the switch of the PSU from the back. Turning on the PSU again, turning on computer.. again.. I can get to the BIOS or to the "please insert bootable disk" line but soon enough, 20-30 secs into boot up , screen doesn't get feed anymore from the compuer and goes into sleep.
All the fans keep working when this happens.. and they all do indeed work: CPU Fan works, Graphic card fan works, the 2 fans of the Chasis work. The small light bulb on the motherboard keeps working. so it's not an electricity issue.
Motherboard: ASUS P5K-SE
CPU: INTEL Quadcore Q6600
Memory: 4GB Kit DDR2 PC2-8000 5-5-5-19 - OCZ Technology
video card: HIS 2600XT IceQ Turbo 512MB GDDR3 Video Card
Hard Drive:Western Digital WD5000AAKS Caviar 500 GB SATA
PSU: Thermaltake Toughpower W0103 600-Watt Power Supply for ATX 12V 2.2 and EPS 12V
I will be using a temporary optical drive for the OS installation.. but I want to be able to get to that phase first.. Thank you very much in advance.
apparently the issue was indeed related to RAM.. it had a bad CMOS checksum.. the bios had an option to restore it to default and now the computer does doesn't shut itself ! phew.. that was close.. the ram is 2X2GB. I have another issue with the EIDE controller but I'll post in the appropriate thread.