I know that this is a bit of a pain, but I would bread board the system. OR you might try to clear cmos first.
To do this, take the motherboard (with CPU & RAM) out of the case. Place it on something that is not conductive. Hook up a video card, keyboard, and power supply. Now use something conductive (like the tip of a screwdriver) and carefully short out the power on pins on the motherboard.
Same results? Then clear CMOS, try again. After that, start replacing video care, ram, cpu, MB one at a time until it works.
If, after breadboarding it, you get it to POST, then--
-look carefully at your motherboard standoffs in the case, ensure that they are mounted correctly (no extras, etc)
-hook the motherboard back into the case, hook up vid, key, power on.
-if it still works, then hook up one thing, try it
-plug one more thing it, try it (etc, etc, etc)
I hope that this helps, and please post back with info so that we can figure this out! Mudskipper
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