Dead Computer

[imported_fallen]

My Computer won't power on at all. No Post, no Fans, No lights. Nothing.

I leave my computer on all the time, and just have the monitor shut off with powersaving. This morning I moved the mouse, Hit Keys, Shook my fists at it, and Nothing happened. I pressed and held the power switch thinking it might just be some kind of OS lockup, and nothing happened, Unplugged the system, checked power going to the computer, everything there looks fine. I know voltage in is 120volts, and the powersupply switch in the back is on 120volts, and "ON".


I am pretty sure it is one of 3 things:
1. Power supply
2. Motherboard
3. Case powerswitch

Where should I start with troubleshooting? How can I Isolate one of these faults from the others? Or is there something else I may be missing?

 

[mechBgon]

Welcome to the Forums Start by checking that your surge supressor is switched on and its circuit-breaker didn't get popped. If in doubt, plug the system directly into the wall outlet or try a different surge supressor to see whether that has anything to do with it.

If it's not that, could you post some system info (is it pre-built, and if so what brand/model; or is it self-built, and if so what specs)?

 

[Viper96720]

You can bypass the case switch by shorting the two pins the switch is hooked up to

 

[imported_fallen]

Hi, and thanks for the quick and helpful response. The surge suppressor and power is fine. I am writing this on another working computer that I moved to my desk and plugged into the same outlet where the Computer in question was. As far as specs, I built it myself about a year ago:

MSI NEO-875P(LSR) Mainboard ,Pentium 4 (2.8c) Processor
1gig Corsair XMS Memory
Thermaltake Xaser III 1000+ Case
PSU: JGE-450P4 450watt Powersupply
Radeon 9800XT 256Meg Video card
Main HDD 36gig WD raptor, 2 older HD's WD 80gig
Soundblaster Audigy Platinum
Memorex DVD-RW Drive
Mitsumi FDD

As far as bypassing the case switch I tried that, and no luck, so down to PSU or Motherboard right? Is there a way to make a PSU power on with nothing connected to it?

 

[quizzelsnatch]

You could if you had a power supply tester... but, I'm pretty sure you don't. It really does sound like it's the power supply though, do you have any cheap ones lying around that you could use to see if it's the motherboard?

 

[mechBgon]

Hunch: the no-name power supply bit the dust. Do you have another quality-name power supply (Fortron, SPI, Antec, Enermax, Enlight) in the 350W+ range that you could try in the dead computer? Or run out and pick up a new one, Antec SmartPower SL450 would probably be easy to find in a retail store if you need a suggestion. If the power supply did fail, hopefully it didn't take out anything with it

Viper96720 also has an easy-to-test suggestion there (example photo, ooo that tickles! :Q).

 

[imported_fallen]

Ok, while researching this, I found an Antec Powersupply tester advertised. Anyone use this thing? Is it worth the 29 bucks?. I just want to identify wich of the 2 is bad (MoBo, or PS, or if there is something else that I may not be thinking of.) I just dont want to waste 200 bucks buying 1 part and then find that I have to replace the other.

 

[rcomo]

Open up the case. Toouch the outside of the PSU to ground yourself to it. Then, pull the power cord going into the mobo; if there is any greyness in the connector, your PSU is bad. If this is OK, just unplug all your moltex conectors (one at a time) and replug them in. try to reboot without putting the sidepanel on. If no reboot, then check your case manual and mobo manual ti see where the power on plug connects (both the front panel and the mobo itself). unplug and plug one at a time again. Try to reboot. Noluck? your cheapest option is to buy a new PSU and install it. No reboot? See if your mobo is still under warranty; if so, call the manufacturer or just by a new one if not.

Those are the steps I would go through.

 

[imported_fallen]

I am pretty sure you are right aobut the PSU, and just making sure I have checked all options before I spend the cash.

 

[mechBgon]

How about this.

 

[fuzzynavel]

Originally posted by: mechBgon
How about this.

what a pretty picture!!

How about you go to your local computer store without a restock fee.....buy a PSU and take it home...test your stuff....if it works keep it.....if it still doesn't work then take it back!!! use some excuse like your MOBO has the wrong connectors!!! (can't remember is it newer P4's that have different connectors??(I think AMDs have 4 pin power too don't they?))

A little dishonest but it will do the trick!

 

[mechBgon]

Originally posted by: fuzzynavel

Originally posted by: mechBgon
How about this.

what a pretty picture!!

How about you go to your local computer store without a restock fee.....buy a PSU and take it home...test your stuff....if it works keep it.....if it still doesn't work then take it back!!! use some excuse like your MOBO has the wrong connectors!!! (can't remember is it newer P4's that have different connectors??(I think AMDs have 4 pin power too don't they?))

A little dishonest but it will do the trick!

I see your personal integrity is worth less than $80 to you.

 

[tweeve2002]

one way to test a PSU is to short two pins. of shorts, first unplug all the power leads from your components and the motherboard then use a wire to jump the green wire and any black wire. If the power supply truns on then it is still good, if not then its dead. just down leave the pins jumped too long. Most power supplys need a load to work right to long with out the proper load can and will hurt the psu.

 

[uOpt]

[never mind]

 

[Agentbolt]

one way to test a PSU is to short two pins. of shorts, first unplug all the power leads from your components and the motherboard then use a wire to jump the green wire and any black wire. If the power supply truns on then it is still good, if not then its dead. just down leave the pins jumped too long. Most power supplys need a load to work right to long with out the proper load can and will hurt the psu

This is your best bet. Plug a fan or something into a Molex connector and see if it works. If it does, you're 99% in the clear on your PSU and should check your motherboard. I'm betting that's what it is.

 

[tweeve2002]

Originally posted by: Agentbolt

one way to test a PSU is to short two pins. of shorts, first unplug all the power leads from your components and the motherboard then use a wire to jump the green wire and any black wire. If the power supply truns on then it is still good, if not then its dead. just down leave the pins jumped too long. Most power supplys need a load to work right to long with out the proper load can and will hurt the psu

This is your best bet. Plug a fan or something into a Molex connector and see if it works. If it does, you're 99% in the clear on your PSU and should check your motherboard. I'm betting that's what it is.

Hey yeah thats a good Idea, that way it will draw a load and wont hurt the PSU, and the fan should be able to take anything that a PSU can throw at it.

 

[Sam334]

I'm building a new pc, and after reading this I'm going with the Antec case/psu instead of the generic

 

[imported_fallen]

Ok, After a lot of good suggestions I went down to the local computer store and picked up a PSU tester for $19.00. I know this was $19 more expensive than jumping the green wire, but I thought I would be nice to have around for later, and I am a little paranoid about jumping wires.

Problem is the tester says PSU is fine, PSU Starts, Tester lights Green, Fans I have plugged in are spinning, My voltmeter says I have 12.1vdc where the molex connectors are, and 3.3 on the 4pin that goes by the cpu, I assume these are the right voltages, so, I guess Im out a MB.

Now here is the new question: On a Sub 300$ budget with the system listed above, what are some suggestions?

 

[UsandThem]

Originally posted by: fallen
Ok, After a lot of good suggestions I went down to the local computer store and picked up a PSU tester for $19.00. I know this was $19 more expensive than jumping the green wire, but I thought I would be nice to have around for later, and I am a little paranoid about jumping wires.

Problem is the tester says PSU is fine, PSU Starts, Tester lights Green, Fans I have plugged in are spinning, My voltmeter says I have 12.1vdc where the molex connectors are, and 3.3 on the 4pin that goes by the cpu, I assume these are the right voltages, so, I guess Im out a MB.

Now here is the new question: On a Sub 300$ budget with the system listed above, what are some suggestions?

Just get a good 865PE motherboard like the Gigabyte GA-8IPE1000 PRO-G for $85.00 or the AsusP4P800-E Deluxe for $110.00. Every other part of your PC is still good enough to reuse. I would also get a good power supply like the TRUE480BLUE for $79.00 and keep the generic one for a backup unit.

MSI motherboards I would not touch with a ten foot pole.

 

[rcomo]

I recomend this board

http://www.newegg.com/app/View...=13-127-164&depa=0

 

[stevty2889]

You said you were typing this on another computer from the same spot..you could try the questionable PSU in that computer as a more realistic test than the PSU tester..or if possible try the PSU from that computer in the one that won't start. Did you try clearing the CMOS yet? Or removing the motherboard from the case to make sure it isn't shorted to the case?