PC Hardware Help

Ok, recently I decided to upgrade my computer with a new motherboard and new processor, wouldn't be that dificult since I have already built 3 computers (nothing big, I know.)

Anyway, after installing the MB, processor and heatsink/fan, connecting the power supply and IDE cables I went and tried to start it up. The computer appears to start up, all the fans started up, but then a get a loud system beep (continous) and the fans die down and the computer turns off. Nothing ever appears on the monitor and nothing I have done seems to fixe the problem.

Now, here are the specs

thermaltake Xaser III case (put this on cause the restart button has fallen off, but that wouldn't casue this kind of problem, would it? it didn't on the old pc/mb)
Antec 480 power supply (replacing the original thermaltake 480 watt ps)
Abit NF-7 S nforce 2 mb (replaced a soyo kt333 ultra plat)
AMD Barton 3000 333 fsb, (replacing an old AMD XP TB 2200)
Alpha Heatsink/Fan combo (new one, but used the exact same on old combo also.)
3 pc2100 512 sticks of kingston ram (i highly doubt this is the problem, as I have had ram problems in the past, and it doesn't cause your computer to shutdown right after start up)

Then just the regular old hardrives and cdroms.

Anyway, I am completely lost, I don't know what could be causing the problem, but I strongly feel it could be the motherboard or processor (both appear fine and there are no burn out spots, or bent items, I have also flashed the bios once (tried it w/ out flashing and then w/ flashing) Again this is my plea for help, I am out of ideas and don't know what could be causing the problem.

That mobo has a second power attachment. It is a 4 pin like the P4s use. Did you plug that in?

I was assuming he'd leave RAM settings on Auto, which should set that automatically shouldn't it? If not then yes...

Even if that was the case, I'd still expect it to POST further than he seems to be getting it... I've got some crucial PC2100 that's completely happy @175Mhz, CAS3, default Voltage.

You got any idea about whether it'll detect differing amounts of RAM in the two channels and switch to Single channel operation? Or is this likely to be his problem?

I've heard of people running DC with 2x256Mb sticks and 1x512 stick... Just curious what it'll do with the 3x512Mb.

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<font color=red>Those of you who think you know everything are annoying to those of us who do.</font color=red>

FOC has to be turned off on Soyo boards in bios if your fan is less than 3000 RPM's. If you have a high output HSF it won't detect it and thus will not shut down.