Compaq P4 died

[jigeye]

I was playing around with my older Compaq P4 2.0ghz desktop pc and I was measuring the PSU and was thinking of putting a larger 500Watt one in. While I was measuring it the thing just shut down and now won't start up at all. No lights or sounds. I checked the obvious like the outlet and cord and they are good. I tried checking the plug with a multimeter while it was still plugged in to the board and I don't get any voltage readings from any. Did the PCU for sure go bad? The PC was still a good one for surfing the net and I was hoping to upgrade the graphics card so I could use a larger LCD monitor. Any ideas?

Thanks,

Jigeye

[spearchucker]

My guess is that you shorted something out when probing the PSU with the voltmeter and blew a fuse in it.

If you get it running, you shouldn't need a new video card just to run a larger monitor and PSU should be good enough to run a low end card.

[jigeye]

When the system crashed I was measuring the old PSU which is only 200W and is 6 years old. It is possible I shorted something out when I touched the metal housing with my tape measure (i know, stupid thing to do). I probed the leads of the connector to test voltage after the crash and did not get any readings.

Jigeye

[Whoaru99]

If you had the PS disconnected from the computer when you tried to measure it, it's probably blown/fried. Most commputer PS require some sort of load on them when powered up or they blow.

As far as getting a new PS, I probably wouldn't go overboard on the watts. I have a computer that's probably a bit more juiced up than that one (Celeron D OC'ed to 4GHz, two HDDs, two optical drives, nVidia 7300GT graphics card running 1920x1080 on a 23" LCD) and it works fine on a 380W power supply.

[spearchucker]

That would be my guess. Unplug the PSU from the board and test the voltage to see if you fried the motherboard or the PSU. Take the power supply apart and look for a fuse that is blown.

If you can't fix it, I would just scrap it. If you get it fixed with a fuse the upgrade you were talking about (PSU and Video Card) would hardly be worth it on that old of a machine. You would be better of spend $300 and getting a really cheap new PC. It would be much faster than your upgrade.

[Whoaru99]

DO NOT DISCONNECT COMPUTER PS TO CHECK VOLTAGES.

Many (most?) need a load on them when powered up or they will blow.

[jigeye]

Yes the PSU was still plugged in when I checked the leads for voltage and did not get a reading. I will try a new pwr supply first and if that doesn't work I'll just build a new system using the old Compaq case. Sounds like more fun too.

Jigeye

[spearchucker]

DO NOT DISCONNECT COMPUTER PS TO CHECK VOLTAGES.

Many (most?) need a load on them when powered up or they will blow.

It is already blown or the motherboard. They won't blow up, but may not put out the right voltage without a proper load.

[spearchucker]

If you build a new one, I would make sure that the Compaq case is a standard size. Compaq used to use some non-standard sized motherboards and PSU sizes. Make sure it is ATX.

[jigeye]

Good point. I'll make sure to check the case size first before I start.

Thanks,

Jigeye

[Whoaru99]

They won't blow up, but may not put out the right voltage without a proper load.

Actually, many will blow up (well, not really "blow up") but will cease to function if operated without a load. Some have small built-in loads, but some don't, and those will fail if used without a load.

[jigeye]

Yes you are correct. I made sure it was still hooked up when I checked the leads and there was no voltage at any of them. I also took it apart and checked for a fuse but couldn't find one. It's junk I think. Will let you know what happens when the new power supply comes in.

Jigeye

[jigeye]

So my Compaq is back in action. Installed the new power supply and if fired right up. Works good. Guess I won't need to build a new one after all. At least not for now. Still sounds like fun though.

Jigeye