Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations strongm on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

Computer Won't Turn On! 4

Status
Not open for further replies.

included

Technical User
Jun 11, 2005
29
US
When I got home from school today, my desktop (which I never turn off) is off. I figure my mom's been using it or whatever and turned it off, so I go to turn it back on. I press the button, my computer comes on for a second, then goes back off. My keyboard and mouse are still on though, and when I press the button again, nothing. So I turn off my power supply, turn my power supply back on, press the button again, and the same thing happens.

There are no beeps, or anything. I've tried disconnecting the hard drive, and doing it all again with the same results. I've tried taking the motherboard battery out to reset my BIOS and CMOS, and still, the same thing. I built my desktop, so I don't really have Dell tech support to call or anything. I'm freaking out, I don't know what to do. PLEASE help!
 
Check the heat sink on the CPU, make sure the fan is spinning and that it's secure. Same with the power supply; make sure the fan is working.

Your problem is *usually* caused from overheating. Make sure there's no dust bunnies in your CPU heat sink as well.



Just my 2¢
"Life gets mighty precious when there's less of it to waste." -Bonnie Raitt "Nick of Time"
--Greg
 
Percentage guesstimate, PSU every time (failed on one rail)

Martin

We like members to GIVE and not just TAKE.
Participate and help others.
 
My money is on the PSU too. They are relatively inexpensive (get a decent one, ~$50) and it is always good to have a working spare. there are PSU testers available that are cheap, make sure you get a 20-pin:


or 24-pin:


as needed to match your configuration.

Tony
 
Ok guys, here's another one to look over. A few days ago (I just found out today), my mom's computer did basically the same thing. We've not had any power surges or anything that could fry both of our PSUs. So that, too, has me baffled.

Anyhow, on the note of it possibly overheating: it's been off for at least 9 hours, and still, the same thing. So I don't think it's from overheating.

And about getting a PSU tester, I'd have to go to the next county to Bestbuy to get one, and my mom called them and they said they'd look at it and give an appraisal for free, so I was wondering if I should just take it in and let them look at it,and hook it up to their tester and such rather than buying one.
 
Free is good. :-D



Just my 2¢
"Life gets mighty precious when there's less of it to waste." -Bonnie Raitt "Nick of Time"
--Greg
 
Don't forget, surge protectors wear out:


There is no forewarning or visual indications given - just failure. And while failing, they can reach very high temperatures, and actually start fires.

There are "suicidal" protectors that kill themselves after every surge to prevent this. A circuit breaker on the strip also helps.

Free is good.

Just make sure they understand that they will be handing the broken PC back to you in one piece in the event you do not want them to do the repair. I am such a cynic...

Tonyh
 
I'd bet the PSU is out like everyone else mentioned but before you take it over to Best Buy (they may look at it for free but they are going to do everything in their power to get you to pay for something) get a can of compressed air (or if you have an air compressor set it the lowest PSI) and blow out all the dust inside the case, CPU area and power supply.

That COULD be a problem and one very easy to fix before you drive across town to get to the most expensive place on the planet for PC repair and parts. Best to eliminate the easy (read cheap) stuff first. I read someplace that Best But will charge $99 to come to your house and hook up a keyboard and mouse! I almost laughed myself into a coma!

Cheers
Rob
 
I too bet it's the power supply that bit the big one. I'd have best Buy test it. Be very firm with them AFTER they test that, unless they have a VERY good price on PSU's you do NOT want one. And don't let them install it, unless you don't feel comfortable doing it or don't know anyone who could do it for you. Then if there are no other computer stores in the area, go on line and find the same power supply or something close and order it. Some places will even have free shipping (if you can wait that long).

 
I swear is the best place to find your cheap PC parts! By cheap I mostly mean cheap in price, you still gotta know your brand names to get the good quality.

Cheers
Rob
 
Well, I took it in to Bestbuy yesterday, and the guy said they'd have a look at my capacitors and mobo and see if anything was obviously blown (which I'd already done) for free, but to get the to do a full "diagnostic" test on it it would be $70... And their test was simply trading out components one-by-one until they found the problem one, which I can easily do myself. SO I guess that's my next step, and then to newegg or pricewatch for w/e it is that I need.

Anyhow, something that baffled me yesterday morning: after having the computer only come on for maybe 1.5 secs all night tuesday night, wednesday morning the computer started up fine, fully booted and everything, and then after about 5-6 minutes of running, out she went again, dead as could be. Could/would this happen even if it is the PSU?
 
included said:
Could/would this happen even if it is the PSU?

Yes. After PSU heats up it goes wonky, typical bad PSU behavior.

included said:
but to get the to do a full "diagnostic" test on it it would be $70

Aha! Again the cynic is vindicated! You have saved a few of your brethren from this same waste of time.

Since the consensus is the PSU, start there. makes one of the best, but Sparkle, Seasonic, OCZ and Nexus (truly silent) are all good brands. Google "power supply calculator" to see what your needs are.

Thanks for the update.

Tony
 
Thanks for the advice and the link. Any info on how good an X-Connect PSU is? I want to go modular, any other recommendations, other than X-Con?
 
There is an argument against modular in that more connection points = more resistance and another point of failure. PC power states on their site:

Due to their look, convenience, and cost savings for manufacturers, modular plugs have become a popular power supply feature. Unfortunately, there has been little or no discussion of the impact of this feature on overall performance and reliability. The fact is, modular plugs limit power by adding to electrical resistance. The voltage drop can be as much as would occur in 2 feet of standard wire. Worse yet, modular plugs utilize delicate pins that can easily loosen, corrode, and burn, creating the potential for a major system failure. That's why professional system builders specify uninterrupted wire!

This is their opinion and I respect it, and have no evidence to the contrary. I think X-connect was the first with this feature but no PSU review I have ever read had good things to say about their quality of power. If you go modular, go with a better brand.

There is a new modular that has screw-down amphenol-like connectors that reduce resistance, I will look it up tonight and post back.

Tony
 
Thanks for the info, but don't worry about the research.

PROBLEM SOLVED!!!

My mother and I went to a local PC store and bought a PSU, more or less for debugging purposes. We bought the only kind they had (small store). Here's a page about it: So far, im extremely pleased with it. The dual 80mm fans have speed control on the back of the PSU, and its very quiet. The only complain I have is that the sata, molex, and floppy connectors are in-line. There's the 20/24 pin mobo connector, the 4-pin VGA one, and two strands, each with 1 sata, 3 molex, and 1 floppy. But I made it work with a bit of cable management. Not to mention the metallic gold looks really good reflecting the light of my cathodes!

Thanks everyone for your help and advice!
 
Also, as for a little insight as to why my PSU was failing. I took it apart, and I found 6 bulging capacitators...

But bad news for my mom's. When her PSU blew, it apparently jolted the motherboard, because not only was her PSU fried, but there are about 7 or 8 bulging caps on her mobo too...
 
Nice to see you fixed your problem, as I said in my first post PSU every time with these symptoms and everyone agreed lol


We like members to GIVE and not just TAKE.
Participate and help others.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top