Huge problems trying to boot PC any help appreciated.

Hi everyone. I hardly know where to start, I suppose I'll start with when I first recognised all was not right with my PC. I had a few problems such as the PC randomly rebooting during 3D PC games and noticed the case was getting very hot just above the PSU.

It was fine most of the time I only had problems playing graphically intensive games. So I stopped playing games and decided to look for an answer to the problem but before I get that far I tried to switch the PC on one morning and nothing happened, it was completely dead.

So I decide not to mess around with anything and hire a local PC repair company to solve the problem. The guy comes out and tells me the PSU is dead and puts in another one. It boots but he can't get on/off switch to work at the front so he takes it away and brings it back a couple of days later.

I spent one evening just browsing the internet, no games, and I notice the new PSU seems very hot at the top of the casing, just like the old one. The next day I load up Lord of the Rings Online and after a couple of minutes the screen goes funny (lots of odd colours on a white background) and the monitor just goes black and I can't see anything. I reboot and eventually get back to the desktop. I think I may have been unlucky and load the game up again. This time the PC just powers down, completely, and turns off. Not like a shutdown it's like it just died and the PSU seems to die with it since it won't switch on again.

The repair guy comes back and tells me a 550 watt psu is not enough to power my ATI HD4890 and that is the problem. I tell him that psu came with the machine. He takes the PC away again and phones me to say I need a 1000 watt psu for this card and he is going to order one. That sounds completely ludicrous to me and I tell him this is an old card it doesn't need anything like that kind of power. He says he already has a 750 watt ordered and he will test the machine with that one.

About five days later I finally get my PC back with the 750 watt psu in it. I am browsing the internet for one night and everything is fine, nothing is overheating. This morning I get up and the PC switches on but doesn't boot. I can hear what sounds like a fan trying to rev up, sounds like a car trying to start (not noisy just repeatedly trying to 'catch'). It eventually boots up then just goes black. The PC is on but I can't see anything.

I turn the PC off and several attempts to reboot are unsuccessful, I don't even get the beep right at the beginning of the boot sequence. Eventually I get an error message, well two, first one that says overclocking has failed (I never overclocked anything on my PC even though the proccessor can be oc'd and the graphics card too I think) then I get a message that says cpu fan error or something similar then I get the screen that says my PC failed to boot and asks if I want to start my PC normally etc. I start as normal and here I am, back alive, for now.

I have absolutely no idea what's going on. I'm not calling that repair guy again. He told me ATI recommend a 650 watt psu as minimum for this card which is utter nonsense I checked their site and it says 500 watts or higher so I'm not letting him go anywhere near it again. I've had this PC for two years with no problems at all up to now if that's relevant in any way. I'm afraid to turn the PC off or even restart it in case I never get it on again.

I'll give you the specs of my PC:

AMD phenom II dual core X2 550 processor 3.1
4 gigs DDR3 ram.
Graphics AMD ATI HD4890
OS W7 Ultimate 64 bit
Hard drive 1tb I'm not sure what the make is.

Any help greatly appreciated.

 

I have to say my money would have been on the PSU as well but 550w (assuming its a decent PSU) should be fine with your spec... Thats not to say that the old one wasn't dead anyway.

Assuming that the new 750W supply is good I would suggest motherboard os on the blink. I assume this is a prebuilt PC? I dont know how comfortable you are working on your PC yourself but i will make a couple of sugestions.

Turn off your PC and open it up. On the motherboard you will see a small "Watch battry". This keeps the power going to your BIOS. Take the battery out for a minute or two then put it back in. This will restore your BIOS back to default settings. I would also suggest you replace the battery with a new one.

Once you have done that try booting up the PC but look around at all the fans and make sure they are working. Also look at your CPU heatsink and fan (It is the biggest heatsink in your case) and make sure they are dust free. If need bee give them a clean with either a compressed air can or vacume cleaner.

See how you go.

 

Thanks Tueur I'm going to have a look at the cpu heatsink and fan in a while. I must say this just bizarre I've never experienced anything like it. I left the room for a while and when I came back the monitor just went black as though a screensaver had come on except I couldn't 'wake it up' at all I had to reboot the whole thing. I got the cpu fan error thing again too so that's definitely my next step.

 

This guy is not a tech man! I'm running a pair of video cards , the i7 930, on a Corsair TX750W @ full load and OC'd. Probably works for the 'I'm not a geeksquad'.rolleyes

 

Still sounds like either power or heat issues. the fan speed is taken from the yellow cable (i think) on the fan power connector. It is possible that the fan is fine but if it has a bad connection on the yellow line then the fan will report as not working. Try downloading and installing coretemp which will monitor your CPU temps. Let us know how hot it is getting.