Compaq Presario SR5123WM turns off halfway through boot

[pcnovice58]

PC was working just fine a few days ago, then this happened.

First, I couldn't get it to turn on so I unplugged the power cord compressed the start button counted 50 times reattached the power cord and it started.

I was attempting to repair it once I figured out something was terribly wrong.  Then five or so minutes into repairs the system shut down.  I've tried this method six times and the same thing keep happening.

The power supply is showing green on the back on the PC.

Now I'm wondering if I need a new motherboard.  The PC is and HP/Compaq SR5123WM and it's nine years old.  And there is no support from HP for this unit. 

But it works fine when it's working.

Please don't tell me I need to trash this PC.  Every picture of my grandchildren and movies are stored in the pc.  At this point I cannot retrieve them.

Please tell me this can be fixed for a moderate repair cost.  It's been the best pc I've ever had.

Thanks in advance for replies.  Help.

[Geek-9pm]

Based on the details you have given, the most common  problems are:
A. Failing power supply
B. Failing RAM stick
C. Failing hard drive.

The fact that the PSU has a green light has little value. There are a number of things the PSU has to do. The green light only means that part of it is on.

This PC is rather old. Have you ever cleaned out the dust? All of the dust?

[pcnovice58]

I've kept the PC clean over the years.

So, there is no way to fix it, then?

[Geek-9pm]

No, you can fix it if  you find out what is wrong.
You test by substitution or elimination.
I forgot to mention, replace  the CMOS cell.
Next, check the BIOS and see if the settings are correct.
Try a good power supply to see if it makes a difference.
Also try to start up with no hard drive.
And remove the DVD drive. Maybe it is failing.
Check the contacts of the RAM  modules.
Even try no RAM and see what it does. It should start and turn on the beeper.

Above are the things most techs would do anyway.
Replacing the Motherboard is a last choice because of cost and time.And you might harm  a new motherboard if thee was some other kind of problem.

[pcnovice58]

OS is Windows Vista.

I figured out the problem - it's the Power Supply Box.

However, I can't get it out of the tower.

I unscrewed all the ones relating to the PSU but it won't budge out of the tower.

Any ideas?

[Geek-9pm]

It is always the last screw you remove.
Look here:
http://www.manualguru.com/hp/compaq-presario-sr5123wm-desktop-pc/upgrade-and-service-guide
Find the page were then show how...

[pcnovice58]

I've looked through 32 pages and cannot find a page that states removal of the power supply unit.

Can you tell me which page, please?  I guess I missed it.  Sorry. 

[Geek-9pm]

Right. The show the back side, but never point out the screws that hold the PSU to the  box. Sorry, I thought there would be a setter view on the read side.

This is best I can find:
http://www.dummies.com/how-to/content/how-to-replace-your-desktop-pcs-power-supply.html
There are about four outer screws the hold the PSU up to that back of the case. The others hold the fan.On a few models there t might be one interior screw to give more support.

You Tube;
https://www.youtube.com/watch?v=7OM3CzGxxyo
Does that help any?

[patio]

There is a latch below the PSU that needs pressed after screws are removed...

See Here...

[pcnovice58]

Dismiss the prior post about not being able to get the box out.

That little screw was irrelevant.

I got the box out with a bit more tugging on it.

Hooray! 

[pcnovice58]

I found a replacement and would appreciate you guys taking a look at it.

I'd like to hope I have the correct one that will work.

http://www.circotech.com/hp-d2537f3r-250w-hp-replacement-power-supply-part-number-5187-1098.html

Thanks.