System: MB: Asus K8V SE Deluxe CPU AMD Athlon 64 +3400 MEM: Kingston 1Gb DDR400 VIDEOCARD: sapphire radeon x800 XT AGP PSU: Nexus NX-5000 STORAGE: 2 sata harddrives+ 2 ide harddrives dvdram floppy+memorycard reader STORY: My computer hanged about a month ago, yellow squares appeared on the screen, and no rebooting and turning on/off would help. First I thought that the almost new x800 video card had died but after replacing it with older PCI card I found out that hard-disks weren't found. So in the following panic I tried to figure out what was wrong, and after testing components was pretty sure that the problem was in motherboard or in the cpu. Tried to install the cpu onto a new motherboard and then the system wouldn't start up at all. Cpu and chassis fans turned on, but nothing else happened or nothing appeared on the screen with either video cards. Then I got myself a spare PSU to test the system with, and it turned on as if nothing had happened, ofcourse xp noticed the new motherboard etc. So the problem seemed to be in the antec sonata 380W PSU. PROBLEM: Then I got myself a brand new nexus NX-5000 PSU. On the box it read 500W but on the label in the unit that is the peak voltage and it should be 460W normally. Ok. It should still be plenty even with all those things inside the machine? So I assembled everything and fired it up. (I had in the panic also cleared CMOS, just in case ) The windows started fine, though it was a bit slow, and then after few seconds it hung. First mouse pointer stopped and then black screen, and no response to anything but power-switch. The fans work, but screen is empty. I tried fiddling around with the BIOS settings and managed to get it to hang even before the windows has started. Different settings seemed to effect a bit on how far it would go on startup. Every now and then I can get even to see my desktop . The funny thing is, that if I start windows in safe mode, it works like a dream Like a safe-mode dream though. Tried to load a restore point, and tried to find every power source settings windows has but no use, it will hang if I try to restart windows in normal mode. I've took out the cpu and checked that I put it in there correctly (never tried that before this event) and applied the thermal paste by the book, (little grain of rice...) and managed to get it run a bit hotter (40C with the rice-grain --> 30+C when spreaded the stuff all around the die). But I think it should not be too hot even at 40?. Also checked that memorystick and video card were properly installed. So, the fact that it runs in safe mode could indicate software problems? Reinstall windows from scratch? On some forum I read that PSU should provide minimum of 18A to 12V rail, and on that nexus it states maximum of 17,5A? Too low for my cpu? I could see my desktop after I disconnected all but the system drive, but it still hanged after a while. Trying to repair windows installation when I have managed to install XP on SATA disk is a bit difficult too, since when booting from cd it doesn't find the system drive. After all this fiddling around different things will propably make it necessary to reinstall windows in any case, but i'd like to be sure that this isn't hardware problem before I go on doing that. So if anyone has any ideas of what went wrong with my computer and how can I repair it, i would really appreciate any help. A friend suggested that the fault still lies on the PSU. Could it be that my cpu eats more amps than the power is capable of. on nexus site it said that maximum load is 15-16 amps...a little low?