I'm looking at a friend's computer which hasn't been able to boot up for several days. With nothing else but the power cord plugged in, the processor fan cotninually runs. The computer is completely off, in fact, won't power on, but the fan still runs. Aybody have an idea what the problem could be?

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Are there any beeps. ?

What happens when you turn it on?? What messages do you get??

There are no beeps and I can't turn it on. I reseated the CMOS battery after doing a little reading online. There is no power to the system and now the processor fan doesn't run. I'm thinking maybe a power surge and possibly needs a new PSU?

Please ask any IT Professional or Hardware Technician before making any such changes in your Computer.

CMOS battery contains information about your computers settings like time and date.
It allows you to boot your computer without entering such information like time and date.
Before resetting your CMOS battery, you would have had other type of problem.

Is the fan worling in the power supply? Are their any lights on motherboard?

try removing all external peripherals.. just leave the power cable on the tower connected.. remove all internal components like pci cards, video cards (modems, video, sound, etc) and then try to boot, if it still doesnt boot try to boot with only one memory connected to the system (only if u have more than 2 memory sticks)... if that still doesn't work. remove all cables from the inside of the tower and just keep the processor fan and motherboard cable connected from the power supply... if there's a dial up modem, make sure that you disconnect it from the tower.. remove it completely. (this is the main cause of problems sometimes and goes undetected. the second main cause could be the memory) try reseating the hard drive too..

Stag, possibly your PSU standby power supply to the mb has failed [without that you usually cannot turn a pc on], else the mb itself has a problem. Okay, there are two types of sys turn-ons - in the old type the power switch is actually a mains switch which turns the PSU on, on the more modern type you press a switch which instructs the mb to turn on the PSU. For this type there must be a working standby power output from the PSU. If the main supply voltages from the PSU are out of range the PSU will not allow the cpu to start processing - not even BIOS will run. If your cpu itself is dead not much happens either. Same with RAM.
So...MB, CPU, or RAM. Or PSU.
Lifting the CMOS battery for several minutes resets BIOS to some pretty basic default settings which should enable your BIOS to run, recognise hardware and report onscreen to you.

Just check the power supply fan if its working or not and than check if the light on motherboard is on or not. If the power supply fan is working fine and if the light on the motherboard is on. Than turn on the computer and see if the power light is on or not.

Try to go into the BIOS setup,if your computer is successfully goes into BIOS setup.
Than check your Hard Drive and connect this Hard drive into other computer and see if it boots normally or not. If it does boots properly in other computer than there is problem with the boot program of that computer.

I'm having a similar problem...

When I turn the tower on, the light remains the standby orange (not the usualy green) the fan runs and speeds up to full. It also won't recognise the keyboard (no lights or response), although the mouse appears to work. There's no output on the monitor.

How is the mouse working if you have no display on your monitor?
Which fan is working, the power supply, the CPU or both?
What light stays on, the front of your box, your monitor?
Please explain exactly what happens when you turn on your PC. are there any beeps, what fans run, what light come on or go off (All), Are there any lights showing on motherboard, can you hear your hard drive spinning, can you open your CD and are there any lights on it?
If you want help you have to let people know what is happening ok!

I'm having a similar problem...

When I turn the tower on, the light remains the standby orange (not the usualy green) the fan runs and speeds up to full. It also won't recognise the keyboard (no lights or response), although the mouse appears to work. There's no output on the monitor.

Which Operating System are you using?
When you turn on your computer ,do you hear any beep sound?
Do you see a configuration screen where it shows your VGA Card and RAM information?
Make sure your Processor Fan is working fine, just open your tower casing and turn on your computer and see if the Processor Fan is working.


Do you mean to say that you can only see the cursor of the mouse on the blank screen?

it is the problem with ur smps try changing ur smps

i have all ready worked on this problem trust me

u may not belive in me as ur fan is workink

this occurs when ur smps goes out of loade balance so try with another smps ull get for sureeeee

it is the problem with ur smps try changing ur smps

i have all ready worked on this problem trust me

u may not belive in me as ur fan is workink

this occurs when ur smps goes out of loade balance so try with another smps ull get for sureeeee

It could easily be your power supply but until you have checked the simple free things, don;t spend money on new hardware.

Ok, thanks for the responses.

Upon pressing the tower power button there are the usual beeps (as far as I can tell) and the power light comes on as Amber on the tower (the sleep colour). Right after I hear a fan come on and speed up.

By the mouse responding, I mean it's light is on and brightens as I move it, there's no output from the monitor at all, just a blank screen. The keyboard won't respond at all (as num lock light won't come or anything).

I'm running XP. The CD tray opens and the loading light flashes when it's closed (no reaction when something's in there).

I'll have a go at opening the tower now, though I'm not sure I'll notice anything wrong even if it's visible...

edit: I couldn't see anything wrong, the fan was working and there's a light on (the aux power light on the motherboard), but then my knowledge of computer compenents is limited to say the least. If you guys think a picture may help I'd be glad to take and upload one.

*awaiting further instructions*

Except for the light not being green or flashing red as the hd works every thing except your monitor seems to be working.
Ensure that the power to your monitor is connected, if it comes from the power supply, get another cord (a lot of kettle cords fit PCs) and plug your Monitor in directly to the power, ensure that the monitor is swithced on at its own switch and that the Video lead is secure. You should get a light on the monitor to work that should change when your PC starts to boot up, before it even gets to windows. If you can not get the light to work your monitor, the monitor is faulty, if the light will not change colour then it is your PC. Either way, I don't think we can assist you here if you can not get a display. We could tell you to change this and that but without testing we are only guessing as to the problem.
One more question, what are the beeps when your pc starts, please describe them! how many and in what combination?

I use the monitor for things other than my PC, so the power running to it isn't the problem. To make sure I plugged in my other monitor, and its power button went orange to indicate sleep too...

And beeps, there's 3 I think. They sound normal. I don't really know how I can describe a beep.

I'm thinking its a virus. Any tips on how to deal with that if it is, would be great too.

Thanks for all your help.

You can not deal with any thing including viruses, until you can get your pc working in some form. I now assume that when you say the lights go orange, you are refering to your monitor??
OK your monitor is working, now is there any change to the lights on the front of your box when you press the start button.
# beeps is important, is it 3 short beeps, or as I suspect 1 long and 2 short.
If is is any other combination, remove your RAM http://www.ehow.com/how_895_install-ram.html, clean it and replace it.
Un-plug and replug in your video cable to from your monitor. While your box is open to clean the RAM, check the cables to the motherboard and drives to ensure that they are fully inserted. Just give them a little wiggle as you push them without too much preasure.

If there is power to the mb the processor fan will run at some speed... your cd drawer will function; the mouse will light up if there is even standby power..
Beep codes will consist of long and/or short beeps, a certain number of each. Search the web for beep codes and your BIOS provider.. eg American Megatrends, Phoenix... I could guess that 3 of any is too many.
Basically, because your monitor is functioning, it means your sys is not. Power off and replug everything you can get your hands on. If still nothing get the voltages from your PSU checked. If they are okay then try with only the mb, CPU and RAM connected [no drives, other cards etc]: still nothing on the monitor? Then one of the foregoing is toast.

These beeps are tricky, over the sound of the fan it's difficult to tell what's a beep and what is just the hard drive. It's very possible that there are no beeps at all. If this was the case, what would that mean?

On the advice already given, firstly, thanks, second, I'm busy tonight, and tbh this all seems a little techy for me so progress might be slow. I'll try and get it done tomorrow.

I'll report back then. :)

It could mean that you don't have any PC speaker attached to your motherboard! It could mean you need a hearing aid! Go to the site I left for you and see how to change the RAM, do that, remove the ribbon leads and power leads going to your hard drive and CD/DVDs. and disconnecft all extra leads going to your PC. That is the internet, speakers, printer etc. Then try your computer again. If you can not get any display on your monitor, you have a serious problem and will need to take it to a repairer. If you do take it for repair, try to find a small one man opperation near you as he will help you a lot more for little charge than a big repair establishment.

Beeps come from the system speaker, and are quite distinct.

can you please help me with my problem which is more or less similar too? it started when i accidentally put my finger into the cpu fan and stopped it for awhile (i leave my cover open because it overheats very often) the computer did not respond so i rebooted and it coud not start up anymore. there are no beeps compared to last time when there was one. and last time i could sense the system starting up when the fan grew faster and stuff, now its just constant when i on it.all the fans and my harddrive seem to be working. my os is windows xp professional. the keyboard, monitor and mouse seem to be fine but the computer is giving no output to them so the monitor stays in on standby. it may have something to do with the fan :-/ im not sure. thats what caused the problem anyway (me stopping the fan for awhile) any help is deeply appreciated

nevermind its ok now :) i press some white button and it booted up ok. relieved now

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