Hp desktop problem just after upgraded graphics card and to Windows 7

[pinoyrish91]

Someone please help me before i go office space on this thing.

ok, so i have a Hp slimline s7520n pc, seemed like a good idea at the time but whatever. For the past two years its just sat in my room broken cause i got a laptop and never felt like fixing it. 2 months ago i decided to fix it. At the time the problem was that it would randomly freeze, shut off, or restart. When i finally opened it up i saw two capacitors were bad so i changed them out with new ones and then my pc ran fine again.

The only thing was my graphics card was going, i could tell by my ridiculously shaky monitor which is a common problem among s7520ns. So two days ago i swapped it out with an Nvidia GeForce FX 5500 pci card i got off amazon. I got that installed no problem and i decided while i was at it to upgrade to windows 7. I ran the windows 7 update advisor before i did anything and it said my system was good to go for the update. Then i installed windows 7 and everything was working fine until yesterday i was watching videos online and i heard a weird sound come out of the speakers and then my system restarted itself.

When i tried to sign back into windows the system kept rebooting itself and the 3rd time it rebooted no picture came on and the processor light stopped flashing. Now the picture sporadically comes on and if im lucky enough to have it come on then when i try to login to windows it restarts again. I checked the other capacitors and they're good. I also tried resetting bios which seemed to work allowing me to run the windows boot repair which said it could not repair the problem automatically. I had to restart after that and now the same problems are occurring again

What can i try to fix this? 

[jason2074]

Make sure the mobo is not giving out on you. Having bad capacitors either replaced and running does not mean its stable. Have gone thru changing Graphics card is one. PSU, RAM might get affected next. Standard Tower has better Cooling System(upgradable) than Slimline. Upgrading to Windows 7 on your system seems to be another issue. This site will tell you more on your Upgrading -->  http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00845986&lc=en&dlc=en&cc=us&product=3199127&key=null&site=null

[pinoyrish91]

Thanks for the info I looked into it but u believe the problem is hardware related. I took apart the whole pc to check individual parts and I noticed that the 24 pin connector from the power supply to the mobo has a few melted outputs. I'm gonna try to splice in a new one but do you think that's my problem for the random reboots and black screens?

[Computer_Commando]

...I noticed that the 24 pin connector from the power supply to the mobo has a few melted outputs. I'm gonna try to splice in a new one but do you think that's my problem for the random reboots and black screens?

Yes, that's your problem.  But more importantly, what is the cause?  Wires don't melt for no reason.
Which ones?  http://pcsupport.about.com/od/insidethepc/a/atx-pinout-24-pin-12v-psu.htm

[pinoyrish91]

Yeah that's my dilemma now. I would assume it was either the power supply or the input for the connector. I'm gonna try to splice in a new connector first but if the problem persists I would assume to replace the power supply. What do you think?

[jason2074]

Either way you will need it for testing. The points you mention on the condition of the mobo,PSU should not be overlooked. Its part of the problem and the cause of the issue and may add another along the way. So make sure that the PSU is replaced coz logically where would the damage come from aside from thermal events.

[pinoyrish91]

I checked the fryed outputs and they were all red +5 vdc. So I decided to open up the power supply and there are three blown capacitors in it. Would you suggest getting a new power supply or could I just do it the cheap way and replace the blown capacitors and the connector?

[jason2074]

Some technicians do it and replace. My old friend(electronic technician) have fix even CRT monitors although he is not a computer technician but is applicable. I personally has some pros and cons cause its a CPU were talking about and not on a TV or any other appliances . Just make sure its the same output and you know the way around currents and voltmeter. Replacing the same capacitors and not subtituted ones or class B.

* The condition of the pins(old PSU) should also be in good condition so the risk as you know is very likely.
* Borrow one if you can.

[rthompson80819]

It won't cost much to replace the blown caps, but keep in mind there may be another reason they were damaged, especially if three went all at once.

[No-one]

Personally, I would just change the whole PSU. I have done PSU repairs before (a lot from the time I built my CNC) but for the cost of what you can get a new one for (arround £10) it ussually isnt work your time. Plus the schocks you get of thos things will keep your arms numb for hours.


Reasons to do it would be if it was an expensive one and to replace it would be expensive ie £90+. If its just a cheap generic item go for the ebay or skip salvaged replacement every time.

Like everyone is saying though this may not be the underlying cause so whilst £10 to get a computer to work again is not much it is just a 30 second diagnostic....

I had a similar problem with mine (no caps blowing though) and they say it was due to non clean contatcs on the board. Weird how it had run for a year...

Still replacing the caps may not help if it is shorting somewhere and then there is TLR's which may have gone which just dont make finacial sense unless you have some kicking arround.

[Computer_Commando]

I checked the fryed outputs and they were all red +5 vdc. So I decided to open up the power supply and there are three blown capacitors in it. Would you suggest getting a new power supply or could I just do it the cheap way and replace the blown capacitors and the connector?

PSU's are cheap enough, get a new one.

[BC_Programmer]

So I decided to open up the power supply

Congratulations. You are TRWTF.