light but no sound on PC

gallantman

Hi,

A neighbor asked me to setup his PC that he brought home with him from the UK. Its not a new PC.

Connected all the cables etc but when I switched on the PC there was nothing !!...not a sound only a small light on in the front.

Apparently it was working before he left the UK but has not been used since - approx 6 months.

What might the problem be or how could I diagnose ? Motherboard ?

I could drop it into a PC shop but I would like to get an idea of the problem / cost before I do that.

thanks in advance,
- gm

P.S. its a large tower type PC, and not the usual brand. Generic brand. I don’t even know what version of operating system is on it.

Gone Drinking

Open it up and make sure everythings sitting in its place properly. Resit the ram and reboot. Failing that, remove anything thats not necessary and try again.

[edit]When you say nothings happening, is the hard drive spinning up? [/edit]

polyfusion

If the PC was transported from the UK, possible that something has come loose in transit. I'd open it up, disconnect and reconnect every cable and reseat the RAM. Connect up to the power again, and see if that rectifies it.

gallantman

OK - I'll open it up and see what I find.

No - not a sound from anything.

-gm

Revvy

If you have a light at the front, then obviously there is power, can you hear the hard drive, fan(s) turning and spinning?
Have you power to the monitor?

When you re-opened it and heard nothing I presume it was powered up

There should be at least 2 cables running from the hard drive to the motherboard, one will be a data cable the other a power cable make sure the power has not disconnected.

There should also be a battery on the motherboard, make sure this has not come loose.

It maybe that something has disconnected in transit.

gallantman

OK - opened it up and could find nothing loose. Battery on the mother board is OK (bios battery ?).

When I plugged in the power supply there was nothing - no fan, etc. 1 light on in the front but the second light with HD underneath it was Off.

Also unable to open DVD and CD - no sure if this is an indication of problem with power supply.

When I plugged out the power supply there was a little whistle sound a sec or so afterwards.

-gm

polyfusion

DVD and CD will only open after computer starts to turn on.

HD light same.

Some motherboards check that fans are coming on when power is connected, so this might be the whistle/whirr noise you're hearing.

Did you check the RAM? If you're not really familiar with PCs, have a look on the motherboard and see if you can find something like a serial/model number, google it, and find out where the RAM is (usually a green stick(s), with black rectangles on it, perpendicular to the motherboard, with a plastic clip either side), and then google to see how to remove and replace RAM.

Any lights on the motherboard when the computer is connected to the mains?

gallantman

I am familiar with PCs but forgot to mention in my last post that I did remove / re-add the RAM.

re: the whistle/whirr noise. I head this when I plug out the power supply not when I start the PC up. It seems to come from the power supply area.

Did not notice any lights on the mother board but I will check again.

gm.

polyfusion

Ok (didn't mean to sound condescending!).

How many sticks of RAM? Might be worth trying to boot without any in, and then with one stick at a time (if more than one stick).

If you still get no response, I'd be inclined to suspect the PSU at that point. Computer should still boot up a bit with no RAM (you'll get beeps) or drives connected.

After that, motherboard likely to be at fault (but less likely than PSU, I'd think).

I've seen faulty PSUs sometimes begin to work if the connection to the motherboard is removed, and replaced, (or even use alternative power connectors to drives), but invariably go back to being bad (might start the PC a couple of times). Maybe the whistle is one of the components in the PSU giving up?

EDIT: Also check the cooling fan at the processor is connected up - usually a small connection with 2 or 3 wires from the fan going into the motherboard.

EDIT 2: Just thought of another thing - any PCI/AGP cards installed? Might be worth removing them too, and if a graphics card, just use the onboard graphics port (if it has it).

gallantman

Hi,

Didn’t think you were being condescending and sorry if my reply implies that. I appreciate all the help I get on these forums.

Only one stick of RAM but I’ll try with it removed. I’ll check the cooling fan. There is a modem and graphics card. I can remove the modem but I think the graphics card is needed as I don’t think there is another connection for the screen.

I am inclined to think its the PSU because of the lack of response. If so, is if just a matter of getting the serial number and ordering a replacement on line ?

- gm.

polyfusion

Yep, pointing towards the PSU alright. They're easy enough to test if you have a multimeter handy and comfortable working with electricity - lots of info available.

Or if you have a working PSU with the same connections to swap into it to test, or test the suspect PSU in another PC - would confirm/eliminate it as the problem.

Same model number would be ideal (might be hard to find), but as long as it has a similar or higher wattage rating, same kind of connections (for motherboard (20/24 pin), drives and processor if applicable), then it should be fine.

gallantman

Hi,

Just to let you know that I got loads of info, video clips etc on how to check the PSU.

Not a trickle from the PSU so got a new one in Maplin for 40 euro.

Put it in tonight and loads of sounds...thanks again !!

- gm