PC Power up problem

Recently, I have encountered a little problem with my PC. When I push the on button the PC seems to power up (lights come on etc) but then it shuts off. I seem to have to now hold the on button for a few moments until the sound of the unit comes on, then let go. What does this indicate?

 

Could be 3 or 4 things. Don't know anything about your PC as you don't have your system spec's filled out.
You could try unplugging the power, hold the power button in for about 10 seconds, release it then plug the power cord back in and start it up.

 

As MrBill pointed out we don't know your system specs, I'd worry about a failing/weak PSU but if you follow the instructions below it will help...

Please enter your System Details. It helps us in answering your questions!

 

Sorry about that, I had entered my spec but forgot to check appropriate box. Try it now.

 

Yep, we can see it now. I'll retract a weak PSU as the issue, although 450w is only mediocre your system shouldn't require near that anyway.

You say it's self built, did you do it yourself or ask a tech?

Either way how old is the computer?

 

I put the PC together and then took it to a tech to run a diagnostic and load the OS. He owed me a favor so it was gratis.

 

It still could be PSU problem, namely a failing PSU, like wildfire points out heaps of power for your system, but depending on how old it is, the PSU could be failing.
How long has it been since you have given the inside of the case a blowout.
hawk22

 

The front panel power button behavior is determined by the BIOS Setup Menu. If me, I would reset the BIOS (see your motherboard manual for specific instructions) then upon first boot, go right into the BIOS Setup Menu to set the date and time.

Your specs say HP 450W for the power supply. Was that a new PSU or taken out of an older HP computer?

I think I would swap in another, known good PSU just to eliminate that from the equation.

As a side note to WF - I wish system specs had a line for "Date of Purchase/Assembly ". Maybe you can rattle some cages for that?

 

The PSU was new when installed and the PC is about 4 years old since the original build although there have been upgrades. Thanks for your suggestions. I will try the BIOS reset and maybe look for a new PSU since I am thinking about swapping my Motherboard out for something a bit newer and faster.

 

You might just consider replacing the motherboard's CMOS battery. After 4 years, it may be getting weak. Unplug from the wall, touch bare metal of the case to discharge any static in your body, then remove the battery and take it to your local battery/watch/camera counter for a replacement. They only cost a couple dollars so if not the problem you are not out much. Most counters will recycle your old battery, which is good. And your travel time with the battery removed will be more than enough to reset the BIOS in the process.

Do not touch new battery with bare fingers. Skin oils promote corrosion and attract dust. I put a clean sock over my hand.

As far as replacing the motherboard, understand in terms of software licenses for programs you have purchased (Window, Office, and anti-malware solutions), a new motherboard is considered a new computer and unless you have full "Retail" licenses, you will need to buy new licenses for your programs too. That is, OEM licenses are not transferable to new computers (or upgraded motherboards). Just something else to remember when figuring out your budget.

If serious about getting a new motherboard, I would hold off on buying a new PSU if you can until you determine the power requirements of your new motherboard, new CPU, new RAM and new graphics solution.

 

Never saw a CMOS battery cause this problem. I have a PC that is over 12 years old and has the same battery in it the day it was built. CMOS batteries do last a long time.

 

Sorry Bill, I have (though I'd expect to see time/date problems also). Yes batteries can last as long as you posted but generally they fail at ~5years. MrBill's advice is good, for a matter of a few pennies Joe could resolve the issue and if not it's only a few pennies.

 

Lithium Ion batteries are supposed to last about 10 years so your 12 years is good.

But, Man created these batteries so not all are perfect. I have seen batteries fail within 3 years. I use the same 2032 batteries on my bike computer and it lasted about 2 years. I have even had one that was bad right out of the packaging. So failing at 4 years may be sooner than average, but still not uncommon.

As far as the CMOS battery causing this particular problem, I have not seen it either. However, as I said earlier, the function of the front panel power switch is set in the BIOS, and can be changed by the BIOS Setup Menu - and of course, changes are saved in the CMOS memory chip. The settings are typically instant off, or hold for 4 seconds for off with less than 4 seconds suspending the computer. But his behavior is odd that might indicate a corrupt setting in the CMOS - and why I initially suggested resetting it.

I simply suggested the battery when the age was said to be 4 years because $2 is a lot cheaper than a new motherboard, CPU, and RAM - and easy to do.

Not sure what MrBill suggested that cost any money. Confusion between MrBill and Bill?

His suggestion was to "...try unplugging the power, hold the power button in for about 10 seconds, release it then plug the power cord back in and start it up. "

And too that, I've seen it suggested before but I have never seen it do any thing myself. And I have never been able to find any published document (tech manuals or ATX Form Factor Standards) that says unplugging and holding the power button for 10 seconds does anything. If anyone knows of such (not another forum poster please) I would sure like to see one if anyone can post a link.

 

Don't know about any manuals, but I have done this and have seen where other people have done the unplug and hold button in trick and it works. Seeing/doing is believing in my book.

 

And what is that suppose to fix?

What I know is that PSUs are required by the ATX Form Factor standard to supply +5Vsb standby voltage across several points on the motherboard whenever the computer is shutdown, but the PSU is still plugged in (and, if equipped, the optional master power switch on the back of the PSU is set to on).

This +5Vsb is used for many "Power on" functions, like Power on LAN, Power on Mouse, Power on Keyboard, and it provides "soft power" to the front panel power button.

Unplugging the power cord ensures that +5Vsb is removed from all circuits and bleeder resistors throughout the system quickly drain any residual voltages held in capacitors.

So I can see unplugging and that has worked for me on many occasions, in particular with network settings. But holding the power button? I don't see what it does once that +5Vsb is removed. I think it is the unplugging that does the trick. I could be wrong, for sure - and that is why I sure would like to see it documented somewhere.

 

I am done with this post. I know what has worked for me and others. I am not the doubting Thomas type.

 

@MrBill - please understand I mean no disrespect and nothing personal. I am not a carpenter, a banker, a medic or a mechanic that just happens to be interested in computers. I've been an electronics technician for over 40 years - fixing air traffic control radios, stereo receivers, tape recorders, VCRs, TVs, microwave ovens, and computers too. I've taught electronics theory and I trained others how to fix various electronics systems. So I have a keen interest in, and a pretty good understanding of how electronics hardware devices work.

But, electronics technologies are constantly evolving so to stay current, I must constantly keep learning. And that's all I am trying to do here.

There are many "tricks of the trade" - some valid (like pulling and re-inserting cards and RAM modules to scrape dirty contacts clean), some are old wives tales, some are just what in my old radio maintenance days we used to call "FM" - for a certain kind of magic (which often leaves room for some tricks - like foil on rabbit ears, or wrapping a broken hard drive in plastic and stuffing it in the freezer - which actually worked - once - for me).

You are not the first to mention this trick, nor the first I have asked for some references. I was just hoping you would be the first to provide one.