Other PC won't boot, weird electrical problem.

Basically, over the last few days, after I shut my PC down, the speakers would start making a pulsing constant thumping sound while my mouse and keyboard would flash every second or so. this would go away after about 1 minute and it would shut down and boot up fine.

Now however, it does it whenever my PC is plugged in with the power on, meaning that I can't boot my PC at all. Any help would be greatly appreciated.

 

Start by pulling out every usb device and the speakers then try booting. If it boots then gradually add all the stuff back in and reboot each time. This might be able to identify what bit is causing the trouble.

If it's still the same then possibly check the PSU, it sounds like it's holding a charge and dumping through the mobo.

 

My money is on the PSU. If its dumping a charge, i'd replace it lol. Before it dumps a charge that kills something.

 

I've tried the first suggestion to no avail. I haven't tested the PSU theory yet so I'll do it tomorrow because I'm going to bed in a minute. I did put my hdd in my spare PC and it makes it through the splash screens but BSODs at the welcome screen. Is my data salvageable if I get a new hard drive?

I'll post tomorrow after I've tested the PSU by using the one in the spare PC. Thanks for your help so far guys.

 

It could also be the case that shorts something... Might want to remove the motherboard from the case, put it on a table for a quick test. If you have a custom heatsink, be sure to be careful when you manipulate the board, you don't want to break it from uneven weight.

 

Alright. Out for the morning but I'll test it all when I get back.

 

try to unplug the psu from the board leave it for a while then recheck again
check your psu first
then check your board
shortcircuit? maybe

 

I can say that it's not a problem with a case. Unfortunately however, my spare pc power supply is only 405W which I'm not sure is enough to power an 8800GTX, Q6600 and 2GB of DDR2 RAM. I can't tell if it's the mobo or the PSU because of this. Which would it be more likely to be? And would anyone be able to provide insight with the HDD issue? Thanks.

EDIT: Just managed to plug my broken HDD into this spare PC by stealing the SATA power cable from my DVD drive. It does work, so I assume it's a problem with my Windows install. I'm going to try repairing it in the morning. I'm currently backing up my documents etc to this PC and if repairing windows fails then I'll just have to reinstall windows. I'll get a new HDD anyway for backup etc, which I was planning on doing in a couple weeks anyway. >.>

EDIT 2: This is the BSOD screen I get if I try to run the HDD that BSODs at the welcome screen (from my main PC) trying to repair the Windows install yielded no results, W7 found no problems to repair.

 

Stop error 7B means inaccessible boot device.
You cannot simply transfer a disk with windows installed between two systems and expect it to boot from that disk - unless both systems are identical enough with regards to hardware config. In your case the motherboards are most likely too different - or the disk controller is too different or in a different mode (ahci vs raid, etc). In this case changing bios settings could help.

If you aren't trying to boot from the disk you have just moved, you need to check the hard disk order in the bios setup menu (typically somewhere in the boot submenu) and change them around as it looks like it is currently booting from the wrong disk

 

That BSOD is from trying to use it as the boot drive. If it's not used as the boot drive, it works fine. So if I fix my main PC that HDD should still work fine? I'll get a 1TB anyway because I'm running out of space and a bit of backup never hurt anybody.

In regards to the other problem, We're fairly sure that it's a PSU problem but I have no way of testing it. Shall I just bite the bullet and get a new PSU?

 

Yes, I would expect so

I would use the PSU of the 2nd PC on your main system. True, 405W may not be enough to power the system at full load, but it should be enough to boot and get to the desktop. Even if it isn't, the worst case scenario is that the PC will not boot or shut down during boot, it is highly unlikely you could damage your components by using an underpowered PSU.

 

Alright, I'll test it out a bit later. Thanks for the help.

 

Alright, tested with the spare PSU. The spare PSU only has a 4 pin power connector whereas my main mobo has 8 pin but it booted fine, fans spinning, sensors working as normal etc. Got to the BIOS screen and it gave me a CMOS error (I took it out to try and fix the problem, might as well try it while you're there) and I had to press F1 to continue. I don't have a PS2 keyboard handy and I couldn't be bothered to scour the house to find one. In any case, it booted the BIOS fine, and the HDD seems fine when it's not being used as the boot drive in my spare, so that should be fine too?

Does this mean that it's definitely a PSU issue and getting a new one should fix the problem?

 

If everything else was the same as when you were having issues, and with the new PSU the problem went away, then you can be relatively sure the psu is the culprit. No 100% garantuees though!
If you had already made changes to the pc's config to try and fix the issue, then it would be wise to bring the pc back to the initial state except for PSU and try booting it one more time. The only clear symptom you describe is the noise from the speakers so make sure those are connected and on!

 

It wouldn't let me boot at all. All it would do was make the light on my mouse flicker on and off, the caps lock lights etc flicker on and off on my keyboard and the speakers would make a thumping noise. The mobo lights would also flash on and off. The only thing I did was take the CMOS out because it wouldn't even turn on at all.

With the spare PSU, it booted up as normal and there didn't seem to be any initial problems.

 

Half good news. Got new PSU, main PC works fine. However, the fan on the PSU doesn't work so I'm gunna have to return it and get a replacement.

 

What psu did you buy?

 

If you got the Corsair AX series or the Seasonic X Gold, or POSSIBLY any other 80Plus Gold certified PSU, than it's normal that the fan does NOT spin. It will spin when you are under load.
The reason for this is simple... it's very efficient, so low heat.

 

I got the Corsair GS700, which to my knowledge spins all the time.

 

Ok yea, faulty.