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When I turn my computer on, it attempts to boot up, then after a second it makes a high pitch sound and wont start for 5 minutes or so. The green light in front turns off and the amber light below stays on. After a few minutes the noise goes away and it will finally boot up on its own.. If I unplug it and plug it back in while this is happening it will start immediately...the monitor turns on and computer is fine and will restart ok the rest of the day. This problem only occurs if the computer has been off overnight or for several hours. I changed the powerstrip already thinking it may be bad. Any suggestions?
Your CPU fan may be defective and not rotating at normal speeds, causing overheating. after awile the fan may eventually speed up and start cooling properly. This is all a guess, mind you. Verification is rather simple though. Simply remove the side cover and observe the CPU fan. If this is what is happening it may be due to dirt and dust in the fan and heatsink. Try canned compressed air to blow out the dust. When inside the case, look at the motherboard for capacitors with bulging tops or leaking fluids. Capacitors are upright cylindrical components scattered around the motherboard. There are many of these and usually a couple of different sizes.
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Thanks for writing. I will try what you suggested but am curious... If the computer is off all night, and this only happens on initial startup, how can it overheat? I think I understand about the capacitors. I would assume you think they may be leaking, therefore discharging overnight and taking longer to charge in the morning causing the delay in startup?
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A CPU heats up very quickly. If your fan takes a while to get up to speed it can overheat. Some motherboards will emit the sqeal or "siren" indicating an overheat situation.
If any capacitors are bulging or leaking, they're most likely blown.
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Dan answered your questions for me. When fans get gummed up they will sometimes run OK after an initial warmup. The clue here, as Dan pointed out, is the squealing noise.
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I agree that it's the CPU fan. I suggest replacing it. You might get it to work for a while by cleaning and/or oiling, but replacement with a ball bearing fan is the best solution. They are usually easy to change.
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I'm told there are 2 fans. One on the hard drive and one on th epowersupply. Which one are you referring to? Can I replace either fan seperately?
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Hello, most computers have at least two fans - one is part of the power supply unit and the other is seated on top of the CPU chip (on the motherboard)... it's the one on the CPU chip you need to look at/replace.
Open up your computer case - it's very easy to identify.
Windows 98SE
HP Pavillion
Celeron 533MHz
HDD 10GB + 4GB
64MB RAM
Antiquated & Poor Quality
Runs like a dream.
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As Tryan pointed out, open your system case and look for a fan on top of one of the largest components. A small (approx. 2" X 2" or so) fan should be evident on top of, or on the side of, the heatsink which covers your CPU chip. If your system case has two side panels, it's usually the left hand panel you should remove. If it's a one piece cover, well that's self explanatory.
The squeal (sorry for my spelling in the previous post, brain going faster than my fingers) is usually emitted by the CPU fan not running or running too slow. It can be connected to the motherboard via a small two or three wire connector, or, powered by a connector "in-line" with one of your hard disk or cdrom drive power connectors.
The fan is screwed down to the heatsink or held in place with a clip assembly. (The former is most prevalent.)
In cases where your budget is small, you can usually peel off the label on the center of the fan hub, spray some WD-40 or similar solvent in to free things up, then put a few drops of electric motor or lite oil into the hub to give it temporary new life. Wipe off any excess oil and cover the center hub with a piece of electrical tape to re-seal the hub. I've done this on a few CPU fans and power supply fans.
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I must say thank you for all of your help. I will follow your suggestions when I get home and repost the outcome. Thank you all.
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If you are still in trouble take the RAM in and out a few times which will clean any oxide off the edge connectors. Check seating of all connectors while you are in there.
Derek.W
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This is where I'm at. I took the cover off the computer as suggested and this is what I noticed. When I power up the computer the cpu fan does not turn on. The other fans do turn on. After about 5 minutes, the cpu fan does turn on by itself and then the computer will boot up and is ok. I plugged a new fan in and the same thing happens. Should the cpu fan turn on as soon as I power up the computer? Any more suggestions.... It seems your advice thus far is heading in the right direction but I don't think both fans could be bad. Could it be something else keeping the fan from turning on? Thanks, Mike
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The fan is worn out. The easiest thing for you to do is to purchase a new heatsink/fan unit in a size suffiecent to cool your processor. These HS/fans are rated by the processor make and model. The noise level is usually part of the specs. The higher the Db rating the noisier. If you have a local computer store I suggest you either take the computer there or at least buy a HS/fan there. You will also need thermal paste. It sounds like you don't know alot about computers so it may be best to let someone else fit a new HS/fan to your processor. There are some things that could go wrong if you don't know the proper proceedures. If you feel you want to tackle this anyway post where you live and what processor is in your computer.
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OtheHill
The poster said (#11) "I plugged a new fan in and the same thing happens". Any thoughts, I can't quite square this with your suggestion in #12?SIWORKS
I might have wondered if you had a bad joint on the fan supply output from you power supply, that took time to "break down" and connect after power on. As you have already replaced the power unit this presumably is not the case.The only thing I can think of is that the fan is intentionally delayed until a specific temperature is reached. I've never run into this before but it's just possible I suppose.
Did you try my #10? Check seating of all connections inside the box while you are in there.
Derek.W
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Derek
OK, I missed the new fan statement. This is indeed puzzling. Seems to be functioning like a laptop.
SIWORKS
The CPU fan IS connected to the header labeled CPU isn't it?
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In response to #13, yes, I did try a new fan and the same thing happened. The computer wont boot up until the fan turns on.
Yes I did try # 10 and all appears to be fine. As for # 14, The fan is plugged in where it always has been.
I still dont understand why if I unplug the computer and replug it in, the problem goes away for that startup only. There have also been instances where the computer wont start at all unless I cut the power to it and restore it. I'll turn the power button on and it will shut down completely after a second.
I think I mentioned this all satarted after i ran the computer in safe mode and did a defrag. I left the computer on th defrag, and when I got home it was off. When i tried to start it, this problem occurred and has been there ever since.
If any of you would like My phone # let me know. I do appreciate all the help. I'm in staten Island new york.... any good repair places you could reccomend would be nice. thanks, Mike
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Aha, your phone number offer made me chuckle. It's a big ball we all live on and there's a lot of land in the sea with various forms of life on it LOL. I'm from the UK.
Not much help but my guess is that you have a defective motherboard. I have had situations when the power supply appears to have shot but it is actually awaiting a low voltage signal to be back fed from the motherboard to fully initialise the other supplies from the power unit. This happened to me and was quite confusing. Could be a capacitor or any other component on the mobo for that matter.
Unfortunately the only way to prove/disprove this idea is to change the board. To some extent if you have changed the power unit, fans, and checked connections/cables then there is little else left to assume.
Derek.W
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I'm afraid I have to agree with derek. The clincher is when you stated that if you unplug and replug the computer you can get it to work correctly. The only other thing I can possibly think of is to unplug and replug the 20 wire power connector from the motherboard a couple of times to clear any possible corrosion. Do this while unplugged from the wall. Enter the BIOS and set the power management to no suspend on anything. It does seem the MBoard is at fault but it can't hurt to play with some settings.
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.... just to add that in my case it was a "solid fault". By that I mean the backfed voltage from the mobo never arrived. Voltages on the power board vanished about half way across the board at a chip. It would turned out that this chip needed to be activated in order to initiate the other power supply voltages.
It is very well known for temperature to affect hardware situations. When you have a fault the difference between "go" and "no go" can be a disconnection of microscopic proportions.
When you switch the computer on in the morning it will then start warming up to some extent and there are voltages present. Either or both of these might eventually cause a break through across a poor connection (perhaps inside a component). This could be quite sudden. I spent many years TV servicing as a hobby and have seen much of this sort of thing. Intermittent faults were always the worst to locate.
You could peer hopefully at the underside of the board with an eyeglass but even if the fault is a bad joint and not a component you will probably have little chance of spotting it.
There is one thing you could try (please don't laugh). Leave the covers off overnight and when it doesn't start, tap around gently on the motherboard with something like a paintbrush handle, or even the brush end (trade jargon - vibration testing). If it should suddenly break into life then at least you might have some idea of the area on the board where the problem lies.
All this is just ideas of-course but right now I can't think of a better guess than a mobo fault (of some description).
Derek.W
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Thank you Derek and Othehill. I will give it one more try as per your suggestions.... if all fails I will just send it out for repair locally... YIKES! Thank you once again for taking the time to help.... If I send it out, I will at least understand whats getting done. I will repost with the outcome either way. Have a great day, Mike
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Yes, please post back. It's not always easy trying to work out things remotely. If you do hand it it in they might unearth something none of us thought of....
Derek.W
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