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chukrox

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Flakey power switch

My one year old ATX P2-233 has a problem with the power switch on the case. When the PC has been turned off for a while and i try to turn it on, i have to push the button 5-15 times before the machine actually comes alive. When i power down the system completely and then turn it back on it comes on immediately. This problem has existed since i bought the machine but it never really bothered me because i usually leave it on 24/7. I no longer do that and the problem has become quite annoying. Anyone know whats going on?

System specs:
P2-233
Asus P2L97 mainboard
ATX case/power supply
32 megs
8.4 Maxtor (3rd one)
ATI Xperts@Play AGP 8MB
SB AWE 64
USR/3COM 56K Voice
Toshiba DVD
Sony CDR
Purchased from Zenon (DONT buy from these guys!)

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kschang

Either the switch or the power supply is going on you. I'd suspect the power supply. My 250W just died on me, it used to be a 486 way back when, so it's about 5 years old. Had to open the case and pull out the switch and all that to replace it. Power supply is cheap, just replace it and save yourself the hassle.
Well, it either gonna be the power supply or the contacts at the phsyical switch. I would guess that the contacts at the physical switch is the culript, this is because you stated that this has been a trubba since the get-go.

What to do to remedy this situation? First, I would remove the front cover, there are probably a couple of clips that retain it, and take some rubbbing alcohol or other cleaning solution and wash over the contact switches, if its a dust/dirt build-up this may sort it out. Next, I would check the on/off button itself, see if you can notice anything about it that just don't look right, and see if you can fix it. Can't tell til you look at it.

Worst case scenario, you need to get a new case ($50.00 - $80.00), then all the fun of removing all of your cards, drives, and mainboard, and putting in the new case. If you can do all that yourself, cool, itsa cheap fix, if not, find a friend or a reputable pc dealer (if you find one, let us all know, we're still looking), and they should be able to do it for you for no more than a C note ($100).

I would check the physical on/off switch contacts first though, it sounds as if it was just never hitting right from the get-go, so a cleaning may just do the trick.

GOOD LUCK :-)
That board is an ATX board, so it is using an ATX power supply.  The button on the front doesn't physically cut the power to the board, but momentarily closes a jumper on the board that tells it to send a signal to the power supply to turn it on or off.

To find out if it is the switch, open up your case and swap the connectors for the power supply and the reset switch.  You should then be able to start the computer up by pressing the reset switch, and the power switch will reset the system.  If the problem goes away, you'll need to replace the switch.

If not, it could be a faulty circuit in the power supply, or a problem with the motherboard.  One thing to do would be to go to http://www.asus.com/downloads.asp and check for a BIOS update to your board.  You'll probably want to update the BIOS anyway if you're having the problem where the memory test locks up every once in awhile.  This was recently fixed.

If a BIOS update doesn't help, make sure that the ATX power connector is firmly seated on the motherboard and that all the wires are firmly inserted into the connector.  It sounds like something isn't quite connected properly, but when it warms up, it works.

--
Troy
I wouldn't recommend taking the switch apart to clean as it taking 115v and that usually manages to blast it's own way through a film of muck, also just a little flex the wrong way on the switch spring when replacing it and it could end up popping out and arcing, maybe just causing a little smoke and panic, maybe burning up something. The switch is a pretty standard (In standard cases) item and replacements should not be hard to come by.
Since you say that it doesn't exhibit the problem when the computer is warmed up, that implies that it is not the switch but the power supply. The switch will work as well, or as poorly, no matter whether the computer has been on for a while previously or not. The power supply is affected by being warmed up....it's the likely culprit. The only way I could see it being the switch is if the voltage the switch is sending as the "on" signal to the PS is lower than it should be, and a cold PS doesn't acknowledge the signal as well as it does when it's warmed up.
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ASKER

Sorry i havent replied guys, just got back in town. Thanks for all the advice! My plan is to open up the case tonight and try all the suggestions one at a time (except for replacing the PS) and see what happens. If nothing solves the problem then i will replace the power supply. Expect to hear the results in a day or two and again, thanks for the advice.
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Well Shokwave looks like you may be right. I opened it up yesterday and checked to make sure that the PS was firmly plugged into the motherboard and it was. I pulled the switch to check for corroded contacts and its a sealed switch, cant be opened. I traced the leads back to the MB and they were in good shape and firmly plugged in. Then i swapped the leads from the power button with the ones from the sleep button. With the original power button completely out of the loop the problem still existed which proves that its not the switch. I'm going to replace the power supply tomorrow which (i believe) should solve the problem. I'll let you know.
Well, Chukrox, if Shokwave is right about it being the power supply, just remember that 3 other people suggested you replace the power supply before Shokwave did.  Kschang was the first to suggest it, about 15 minutes after you posted the question.  If it turns out to be the power supply, Kschang deserves the points.

If the power supply doesn't fix it, you may have a faulty motherboard, though it is most likely the power supply.  There is a small chance that a defect in the motherboard is causing the signal not to be sent to the power supply when the switch is pressed.  Hopefully, though, it will just be the power supply (even though it probably costs almost as much as the motherboard, you don't have to rip all your cards out).
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Actually Thoffman you are right, Kschang did mention the PS first (sorry to get your hopes up Shokwave). I just replaced the power supply and that solved the problem. The PC powers up the first time i push the button every time now. Strange thing i noticed about the new PS though, the fan blows air OUT of the case, not into it. I thought it was supposed to be the other way around. Anyway, Kschang, please resubmit your answer and the points are yours. Thanks to everyone for your help.
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kschang

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Adjusted points to 150
Actually, the fan IS supposed to blow outwards.  I work in an office with about 100 PCs, and all the fans blow out.  Are you sure the fan on the old PS was actually sucking air in, or was it spinning, but not blowing enough air to cool the PS and just making it seem as if it was sucking air in?  That fan might have been what ruined your PS.
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I'm sure it was the fan because occasionally the fan would suddenly start making a loud grinding noise and i would have to power-down for a while. Also, i noticed a page at tomshardware.com that mentioned some ATX power supplies do blow out although it should be the other way. Guess i got one of the oddballs.