Desktop PC does not power up on power button

Question

When I press the power button on my desktop, it does not power up completely. Before I press the power button, I see lights on the motherboard. Everything is normal. On power button press, the fans on the cpu, graphics card and motherboard start to spin a little for a second or two and then they stop. No beeps during this process.

It has been doing this for a while now but it used to start up after some trials. Once it starts up, I have NO issues at all like random shutdowns so it is not an issue with OS.

Update: I left the desktop off for a few days and it started.

I'm just guessing here but it seems as if the PSU (Antec TP2-550ATX) is dying out and does not have enough power now - just a guess. It's an old desktop assembled in 2005 but I have maintained it well.

Update: I always keep the desktop running and I never shut it down. During updates or manual restarts, it powers up without issues. I wonder if this sheds lights on the issue.

Any idea how I can narrow down the issue? ex: if I can find if the PSU is dying etc. I'd really like to fix the issue. Please help. Thanks.

Below is the complete configuration.

DFI LAN-Party UT NF4 Ultra-D 6/23 {6.70},
Evercool EC-VC-RE 41/47C,
AMD Opteron 170 2.0GHz {1.3.2.16} 1.312V 36/41C, 
ThermalRight SI-120, Panaflo 120×38mm
OCZ Platinum 2×1GB 200MHz 2.66V 3-3-2-7 1T
XFX 7800GTX 256MB 475/1250MHz {91.31}, 
Zalman VF900 Cu led 41/56C
WD Caviar 320GB 7200RPM 16MB SATA 3Gb/s
Antec TP2-550ATX
Antec P180
WinXP sp3
Logitech MX310
Razer Mantis Speed
BenQ FP91G+ 19" LCD 8ms DVI
Creative Audigy2 ZS {4.42}
BenQ DW1640
Logitech z-5300e 5.1 280W

Legend:
Driver versions: {}
User settings: []
Voltage: V
Wattage: W
Temperature: C (Celsius) min/max

Answer 1

See my answer here : Any way to tell apart a CPU defect from a mainboard defect?.

If you can hear the fans, then it is probably not a PSU problem.
If you do not get any beeps, then it is probably a motherboard problem.
But as it does start up sometimes with no problems, this is an intermittent problem.

The possibilities are endless, and probability is not enough to justify buying any part.

Try to follow the script described in the on-line book link that is in my above answer, to check for RAM problems, bad contacts etc. If you cannot find anything on your own, my best advice is to decide whether you wish to see a tech-shop about it, or invest in a new computer.

Answer 2

I had this exact problem with a Corsair PSU I bought a month ago. It will power on for a second or two, then everything would shut off and it wouldn't even try starting again until I had flipped the breaker on the PSU on and off. Replaced it with another PSU and everything ran just fine. A clear defect in my PSU that caused it to trip its internal circuit breaker after a second or two of power up.

Answer 3

Obviously, try swapping the power supply. If you don't do that, then you may never narrow it down. If you don't have a spare one then a techie friend might.

It's your best hope and maybe your only hope. That's what anybody fixing it would do.

Answer 4

I had problems like this for several months. My computer would boot, start booting or complete booting before the power cut out and it (occasionally) rebooted. Then it stopped turning on at all. I tried replacing the motherboard, making sure there were no shorts between the motherboard and the back case (I had installed an aftermarket CPU cooler and the screws were touching the case). I had tested the power supply multiple times using a procedure provided by the manufacturer and it worked each time the problem occurred again. The PSU eventually failed completely and I was able to RMA it. Keep in mind, though, that power problems can be CPU, Motherboard or PSU related (or even power button related). You should try to make sure that a number of other things are working before you try to replace a part.