So the other day I bought a new (v.quiet) power supply (PSU) for my working computer, however after installing it the screens were blank (it did not POST) or beep although it all powered up. I reinstalled my old working noisy PSU but again the same thing, blank screens.
I'm not sure what the cause is and therefore what the solution should be it. I suspect it could be that:
* My new PSU is 400 Watt , whereas the old one was 350 Watt - could this has blown the motherboard?
* I took the CPU fan off to clean and lifted the CPU & heatsink out of the motherboard - maybe I damaged it (although I was very careful)?
What do you think is wrong with it? Motherboard / CPU or something else?
On two occasions the computer wouldn't power up either; the PSU wizzed round for about a second and then turned off. I checked everything was connected and it does all power up now but no POST.
I even took out the RAM and powered up, thinking the motherboard would start beeping but it didn't.
I'd love to hear what you all think I should do.
If you can post a full list of your specs that would help
So everything was ok before you changed your PSU? Or were there symptoms that made you think you needed a new PSU in the first place? You have more or less eliminated the possibility of a bad PSU since you have changed back to your other one and still can't POST.
If you take the RAM out, the system will never boot since it is an essential part of the POST sequence. At this point I would take out everything in your system that isn't necessary to boot. This includes any PCI devices, your graphics card if you have an onboard solution to use instead.
Try this and if you still don't have any luck, try one stick of RAM at a time in each and every available slot on your motherboard. Then swap your sticks and try the same again. This will isolate the faulty RAM stick if your memory is bad or a slot on your board is bad.
At this point I'm thinking that you may have damaged something maybe on the motherboard or another system component when you were changing the PSU. How did you electrically discharge yourself of any static build-up before putting your hand in the case?
The computer and old PSU were working fine to begin with (just noisy).
Computer specs as far as I can remember:
O/S: Windows XP Home
CPU: Intel P4 3.21GHz (800 MHz FSB)
Motherboard: Gigabyte GA-8IPE1000 Pro2
RAM: 3Gb DDR400 (2x 512mb + 2x 1Gb)
Graphics card: 256mb Nvidia GeForce something or other (supports two monitors)
Sound card: none (in-built in motherboard)
Hard disk: 2x 160GB Seagate SATA 7200rpm
As far as discharging static goes, I touched the metal case and hoped for the best...!
I'm unable to go fiddle with my computer at the mo but I will do what you suggested thank you. It sounds like a good way to eliminate potentially faulty RAM and PCI devices etc.
Assuming that it's not the RAM or a bad slot, what then?