So, if your PC is old or new and it does not boot or has no display then what do you do?
Precautions :
-During connecting or disconnecting devices, be sure to have the AC electrical power disconnected
-Temporarily ground yourself, or use a wrist strap to prevent electric static discharges from destroying certain components.
Here are my troubleshooting procedures:
-With a new motherboard: verify if all mounting standoffs' holes correspond with the holes in the motherboard!!
Or test the motherboard outside the case, on a wooden (non conductive) surface
-Clean the system from dust, then test with the minimum setup:
- Disconnect all peripherals devices (including the drives, CD, DVD, printers and keyboard) and network cables, except for the motherboard + CPU + 1 ram stick, video card, monitor and power supply
-Verify that the 4-, 6- or 8-pin CPU Aux power plug is connected
-Verify that the VIDEO card has a power connecter - if yes, connect the power to it!
Now, power-on your PC. On boot, do you have a display?
-if NO it is one of the connected devices: RAM, Power supply , video card or monitor. So, if possible, swap ram, power supply, video card or monitor - leaving only motherboard and CPU
-test the ram in each slot, sometimes you have abad slot, causing ram problems
-if YES, then disconnect the AC electrical power, and start reconnecting each of the peripherals, devices and cables (one at a time) until the problem shows itself. Before each of these reconnections, you need to follow the precautions above.
*** note : if the fans are running, this shows there is 12 V present from the power supply; this does not mean the power supply is ok, you still need 3.3 V and +5 V as well; and other signals.
Additional tests and things to try :
-boot without ram, it should beep; (also, without video card)
-try the bios default settings, (if possible) or clear the bios by removing AC and the bios battery
-renew the CPU heat paste, and verify that the heat sink is mounted flat on the CPU, allowing for a good thermal contact
-you can also check the motherboard for bad capacitors as shown here :
http://en.wikipedia.org/wiki/Capacitor_plague
- test parts on another PC to know what is ok - and what not - if possible
***note : if you are using 4 sticks - note that many boards do not run well with the ram bus loaded heavily like that, causing deterioration of signal levels and wave forms ! --> so test with 2 sticks max ..
The term POST refers to the Power On Self Test procedure - here a link with a short explanation
http://www.pchell.com/hardware/beepcodes.shtml
Comments (18)
Commented:
The condition where the power supply doesn't turn on at all AND the issue isn't the power supply itself doesn't jump out at me. Granted I don't see this happen very often but I was left with the question. Since then, my research suggests that it's not an often-mentioned problem.
Since then, you told me separately that clearing the BIOS would be a good idea as would checking the CPU pins. These turned out to not be the issue in this one case but here I figure you're more about how to tackle such things.
So now I understand:
I didn't clear the BIOS originally thinking it wouldn't matter and asked: Would it? I understand now that the answer is Yes.
I didn't fiddle with the CPU mount thinking it wouldn't matter and asked: Would it? I understand now that the answer is also Yes.
Author
Commented:that's why you need to follow in this case the bios sequence, and check all partts
Commented:
Sometimes, I don't have an available good matching part (correct socket/gen). But even if I do I'm reluctant to put a possible bad CPU into a good mobo, or even more, a good CPU into a possible bad Mobo for testing, my fear is a failing part could damage the good part I use for testing. Am I just being paranoid? How do you make that decision?
Author
Commented:so the choice is easily made
Commented:
I tend to always replace the power supply first. It's easy, it's cheap and there are generally PSUs on the shelf.
I'd say the same: PSU 95% Memory 5%.
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