No informatin with the mobo for Watts I have had a complete nightmare with building A new pc, got a new MSI MS-6378 (SDRAM M/Board) On-Board VGA / LAN. this was for an AMD duron 700, got it all in set jumpers powered up but no output to the VDU. Looked to me like the cpu (as it was 2nd hand), got a new CPU this time it powered up and came back down, changed the case , same problem tried my AMD XP same thing put it backing to my old PC it’s worked ok. I was informed by fat bloke (electronics engineer) that the motherboard looked duff, sent it back got a new one same problems. With AMD Duron 1.6 powers up no beeps, but still no Video output (and yes I have tried a plug-in VGA card I have tried it, with a 350W power supply. Q; could I need a 400w ???????
Have you tried powering the motherboard on outside of the case...like just on a cardboard box (the m/b one is great)? Do the fans spin? Generally, even crap power supplies should power a system that's pretty lite on parts. If you've got a good brand of power supply (Fortron/Sparkle, Enermax, Antec, for example), you should have no problems with a 300W unit. Especially since it looks like your not putting together a real screamer with bells and whistles with it. You really don't need a 400W PSU with your setup, and I'm not really sure it's the PSU anyway. You can always try another one just to be on the safe side, though. It'll help to elminate potential culprits from the mix.
When it powers up, all your fans spin, right? But you don't get any video output. Does the HDD activity light blink, in other words does it otherwise look like it's booting normally? Also, are you sure the monitor / monitor cable are good? Have you tested the RAM in a different system? Usually when you have problems like that, it's one of a few things... * Jumpers set improperly on motherboard (is the CMOS Clear jumper on?) * Motherboard grounding improperly on chassis * Insufficient / bad PSU * Video card not properly seated * Bad video card * RAM not seated properly * Bad RAM * Bad motherboard Check each of these things to make sure these aren't your problems. Start with the simple stuff first, like making sure the cables are good and connected properly, your components are well seated, etc. Then move your way to the more complicated possibilities.