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New PC. PSU doesn't power on 4

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itsmystie

Instructor
Dec 9, 2005
47
Greetings to all of you!

I've just assembled a new PC but the PSU is not setting on when i press the power switch. Is PSU defective or could problem be elsewhere?
 
Try disconnecting everything except keyboard & graphics card (if not onboard) from the motherboard & try again If ok, connect drives etc back one at a time. Also, try sorting across the motherboard power connector with a screwdriver (rather than connecting it to case) - in case their's a problem with the case switch.

Is the mobo properly seated on pillars? - not shorting.
 
When i used pillars, the ports were not fitting right in their place because the mobo was raised, so i removed them and screwed the mobo directly to case. Is that wrong? If yes, how do i make the ports fit in their position?
 
Take everything out of the case and try it on a piece of cardboard or other non-conducting material.

The answer is "42"
 
Sounds like you have the wrong sized pillars. Generally they are around 6mm, 7mm or even 0.25". Mounting the motherboard directly onto the case will undoubtedly short out a lot of the circuits. Do as Franklin 97355 suggests, and if it all works ok, then get hold of the correct height pillars. If you were using brass screw-in type pillars then if all else fails, they're not difficult cut down with a small hacksaw. or even to file down to size.

ROGER - G0AOZ.
 
1) you might short out circuits by mounting Mobo to case. Not good, but not certain.
2) experiencing similar issue with home built system..there can be a number of causes for the system not to start, as I am learning.
---Bad PSU (happens. Just got off the phone with Antec tech support, and we think/hope this is the case.)
---Motherboard issues: Blown board? Incorrectly attached power swithc? Apparently, unlike older systems, newer PSU's are completely controlled through the Motherboard.

My solution tonight will be removing everything but the fans, repositioning the power switch, and trying it with the current fan and another one. Tech support suggests just cross connecting the PSU from another unit to determine whether it is a board/PSU issue.

No matter how you cut this, it will cost me money. How sad.
 
forgot that switch could be the issue.
Would you please explain this?

"try sorting across the motherboard power connector with a screwdriver"

Do you mean you just connect the terminals attached to the switch with a wire or screw driver?
 
From my session with the (terrific) MSI support people. (I have hit two local support teams in this problem. It's amazing and wonderful)

1) Remove board and run on non conductive surface (Suggested previously)
2) Clear CMOS. Power off, let sit a few moments, Set pins on board to release CMOS (Someone else can explain this better than I). Remove CMOS battery and leave out for five minutes or so. Replace battery.

Good luck to bot of us with that.
 
try sorting across the motherboard power connector with a screwdriver"

jhockey meant to momentairly short the two pins that the case switch connects to. The case switch only makes a connection while it is being pressed"
Good Luck
 
ahhhh.....sHort. That won't blow the board, then. I guess you could also use a connector? Just turn the switch on the back?

THX
 
Unfortunately, this is one of those problems that has about a zillion answers. My answer: take it to the local PC shop, pay them $50 to $80 bucks to assemble it for you. Headache gone! :D

Not that you're not able to assemble a computer. "Dead boxes" happen to the best of us... and without pulling out the voltmeter and oscillator or alternately, replacing every part one by one to see which is the big-badda-boom... there's no quick and easy way (except of course, by random universal circumstance in your favor). :D

---***--- Drew Software offers highly accurate Personality Evaluation software. Reduce turnover. Improve job satisfaction.
 
Well, having connected my own to a second power supply, I can absolutely say it's the Power Supply. Off to Central Computers to get a new one while I return the other.

Other question..anyone in SF know what other component shops there are? SF Computer Systems doesn't seem to seel parts any more (full systems only, they say on the phone), Atman is there (I was never fond of them)..there was one way out on Clement and one down at the end of Taraval (something like Paragon and Acme..but I don't find the names any more.)

Web search for local shops brings up nearly nothing but EBay ads.

 
Hello there! As advised i removed the board and run it on non conductive surface and it worked. Then i started the assembly again but now i did it piece wise, memory and graphics card first, then drives one by one. The PC is now fully assembled and working correctly. Thanks to all of you for your precious advices.
 
The power supply, when removed, had something loose, so that was my main issue. I also discovered, however, thta the rear cover plate (for ps2, usb, parallel port, etc) seems to have been shorting out the board.
 
You can test the basic "does it work" functionailty of the power supply by bridging the green and black outputs with a length of wire pushed into the plug that is normally fitted into the MOBO, this won't check that the voltages are right or that it can deliver enough power BUT if the PSU doesn't kick into life you know something fundemental is wrong... Antec make a relatively cheap PSU tester than I have:

see the bridging wire ;)

PSUs really ned a loading to work properly so this has one!

-

===================================
Transportation Research Consultant
Winchester UK
 
John, thanks for the link re PSU tester. I'm not convinced the Antec tester is going to do more than just a basic PSU check. A 25W load is very small compared to what a PSU is generally capable of delivering. It's been my experience that a faulty PSU may work fine with a light load, but give it some hard work to do and it falls over! The other thing I've found is that the relevant wires are not always black and green. Probably better to quote pins 13 and 14 on a 20-pin connector...

ROGER - G0AOZ.
 
And because the connector uses a different numbering system than just about everything else on the M/B it might be well when mentioning pin 14 to explain where it is, particularly in light of some manufacturers not using a green wire.
With the locking pin down, pins 1 to 10 are left to right on the top row and 11 to 20 are left to right on the bottom row.

Ed Fair
Give the wrong symptoms, get the wrong solutions.
 
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