MoBo Power issue

Clarifications

But if it's an AMD M'Board you could have a incompatibility between the Video Card & M'Board. That's very common even when the M'Board & Video Card are from the same maker or have the same chip set brand on them.

The PS could be on it's way out so I would suggest that you test it with a Known Good one to see what if anything happens.

The Jumper for the CMOS could be set to clear and not allowing the system to actually start.

The CPU could be fitted the wrong way around and not working at all if it's still capable of running

You could have a faulty HDD or other Optical Drive that is pulling the available power low and preventing the unit starting.

You always could have a faulty M'Board but unless you didn't follow normal Static Control procedures correctly this is unlikely unless it's one of the cheap nasty ones.

The CPU from the Old M'Board may not suit this new M'Board.

The monitor may be faulty. I've been caught by that previously and what made it worse was it was my test monitor that had gone bad.

Disconnect all the unnecessary things and just leave the CPU, Minimum RAM and Video Card in place and see what happens when you try to start the unit. If you get a Video Signal you can them try connecting one unit at a time till it stops working. If that doesn't work you can do 1 of 2 things either try another PS or do as I would normally do pull the M'Board sit it on an Anti Static Surface and plug in a PS then connect up a Mouse Keyboard and monitor and short out the power pins to see if it's going to work before you even attempt to assemble it.

I don't like wasting time on hardware I don't know if it works properly before beginning the assembly so I just fit the bare essentials and power up to see if I get a Video Signal and then set the BIOS to what I need. I then power down and fit the M'Board to a case and then go about setting up the system properly but only after I know that it's working first.

Col

The fans most likely run on 12 volts, and so do the hard drives. But the rest run on 5 volts. I suspect the power supply. Not weak, but maybe too low.

Check the CMOS reset jumper.

This is the exact symptom you get if the CMOS reset jumper is set to reset.

Many new motherboards ship with the jumper in the reset rather than the normal position.

Other things to check include the drive jumpers. Western Digital hard drives have a habit of stopping the POST process if the jumper is set to master if no slave drive is present.

Make sure that the motherboard does not have an extra 4 pin power plug. If it does, you may need a different power supply.

Chas

ight sounds like it could be jumpers it could be a bad mobo and possibly a weak power supply, check the little red switch on hte back of hte power supply and make sure its set to 115. Thats what it sounds most like to me. If its on 335 then thats for the oversees power usage since they have a different system of power, if its on that then it would not be drawing enough power from the power supply. If that does not work then my other thoughs would be that maybe the computer went through a power surge and lost its video and hard drive, if this is so you can test it by using a spare hard drive. as far as video goes try to plug a nother video card into it. If all is good when you do that then well you know whats wrong.

Actually just had similar problem with client. Thought it was motherboard, borrowed stronger power supply and oila!, it works. Not sure if you actually tried stronger p-supply, but it could make things pretty simple instead of headache.

A lot of you have talked about video cards. Might I add that the video is onboard and not a card. Maybe that will help things along. Thank you for suggestions so far. Keep them coming.