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Replaced motherboard, now won't power up.

I replaced my motherboard and now the PC will not turn on at all – no noise, no lights.  I tried another power supply and it also doesn't turn on.  I got a power supply tester and both power supplies tested fine.

I was very careful with the install, making sure to ground myself before I touched anything, and setting the parts on an electrostatic bag when I had to set them down.

What could be causing this?

Thanks!
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Snowguy

Check the clear CMOS jumper is it in the normal position?

It would also help to know what mother board we are talking about and the CPU you are trying to use.
It's most likely you don't have one of the cables attached correctly somewhere.  Check that your power switch is connected to the right spot on the board.  Check that the boards power connector(s) (yes, there may be two) are properly connected.

If you're unsure it's the board, try the board out of the case on a piece of cardboard.  Plug in the power supply, your cpu/hsf, Vid card and RAM.  See if it boots that way, if it does, then something wasn't connected properly in your computer.
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ASKER

I have an AMD Athlon 850 (Slot A) with a SOYO VIA K7 motherboard.  there os only 1- 20 pin power supply connector on the mobo, and it will only go in one way.  The clear CMOS jumper is in the normal position.

I'll try removing and replacing the motherboard again.  Then I'll try the board out of the case on a piece of cardboard.

Thanks!
Avatar of BillDL
Put it on the antistatic bag rather than cardboard.
Cardboard can build up static just like human skin and synthetics, etc.

It could be that part of the underside of the board was touching against the casing, in which case this may have caused some permanent damage.

Did it come with a processor already in it, or did you fit one?  Did you seat it properly?

There MAY be a small DIP switch to set up the clock and bus speeds, although there would normally be some life before it burned itself out?
I removed it from the case & put it on a antistatic bag, plugged it in - no power.  So I reassembled it, tried it one more.  This time I got power, the fans on the PSU and processor were going, drives were spinning, but no beeps and no video.
Is the light going to green and then back to amber on your monitor?
I know this is just too simple, but I overlooked it once, I had cleaned the monitor before setting it back up again and had rolled the brightness adjustment wheel around so the screen was pitch black.

Are you sure that the internal speaker is connected to the pin-connector on the motherboard?  It now points to a badly seated graphics card, although I suspect that it was a bad connection from PSU to power-in on the motherboard before.

I have sometimes found that cards have to be "bedded in" on brand-new motherboard slots.  Removing and reinserting the graphics card a few times usually sorts this out.

If you have another graphics card at your disposal, try it.

I have also found that the plate that covers those universal "knockout panels" (to tell you what the ports are) is sometimes too thick, and the female monitor connector doesn't quite push on as far as it should.  Double-check this, because it's given me a few headaches.

There is also the issue of AGP specifications (ie. 2x, 4x, 8x, etc).  A 4x or higher socket SHOULD be backward compatible with a 2x card, but I THINK the sockets have a notch that might prevent a 4x or higher card going into a 2x socket because it might not be supported.  I'm not absolutely sure of this (it might only concern the original 1x and 2x spec), but it is worth considering.

I had problems on a Pentium 4 board where the actual AGP slot and snap-on card retaining mechanism sat too high and stopped the card seating down fully.  I'll find the url for my question here about this before I found the problem, but meantime grab a small torch and have a CLOSE look at this.
no beeps, no video most likely = dead board.
Not Quite, be sure your connectors for for power and reset switch are on the proper pins, and even if they are, turn them around, they could be on backwards. And I know this was said already, but check to see if your clear cmos jumper is on, or if it is on normal. Because all the new motherboards I have received come with the clear CMOS as the default jumper setting.
You could be right about the power or reset connections not being right, it is really hard to tell which way is correct.  And the names on the connectors aren't exactly the same as the names in the mobo manual.

I'll try switching them around tonight.

Thanks!
This question has been classified as abandoned.  I will make a recommendation to the moderators on its resolution in approximately one week.  I would appreciate any comments by the experts that would help me in making a recommendation.

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waffleironhead
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Only the Questioner knows if this was resolved...

MsITech -  you around??  Anything here help?

If MsITech doesn't respond, we can't know so I suggest delete/no refund.
I agree with AlbertaBeef
Sorry I haven't been around.  I really appreciate everybody's comments, but nothing has worked.  It's been sitting there un-touched since November because I got tired of dealing with it.  I boutght a power supply tester and both the new PSU and the one I replaced are fine.  I'm not sure what I am going to do at this point.  I might buy a barebones system and just install my drives and memory into it.  I might have someone else look at it first.

Thanks!
You may want to take the board to a computer repair shop to have the board itself tested. It is not uncommon for a motherboard to come dead, since they are touchy. I just had one come to me the other day DOA. So I suggest that, that way if it is, you can get a new one (if it is still under warantee). Good luck.
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Glen A.
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No comment has been added to this question in more than 21 days, so it is now classified as abandoned..
I will leave the following recommendation for this question in the Cleanup topic area:

accept:AlbertaBeef

Any objections should be posted here in the next 4 days. After that time, the question will be closed.

waffle
EE Cleanup Volunteer
OK!  I tried EVERYTHING!  It wasn't worth messing with any longer.  I finally went out and purchased a new board and processor.  It fit everything except for my memory which I ended up selling at a garage sale.  Thank you all for your help!

Now I have 2  AMD Athlon(Slot A) motherboards, one with an ATHLON 750 and one with an Athlon 850 processor that I'm not sure what to do with.  I don't know if they're bad or not.  I guess I could sell them on ebay listing them as maybe good maybe bad?