Dead PC Help...

jcb33

jcb33

jcb33

Soldato
Joined
11 Apr 2003
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4,158
Location
Notts
Hey all,

I was meant to be upgrading to a new PC but something came up and I was unable to afford it. So my PC which is about 5 and a half years old was to do.

It has never been overclocked and always worked fine, I was just sat browsing the net before work and decided to go and get some food, literaly a couple of minutes later I came back and the screen was saying "No Signal" tried hitting the keyboard etc but nothing.

So I rebooted, I have done so several times leaving a while inbetween with the power turned off and all that happens is the lights come on and the Graphics Card fan stays on max. I smelt no burning or anything but the PC will not start.

Normaly it has the graphics card fan go to max, beeps and then starts up but now nothing beyond the fan.

The PC is an AMD X2 4800+, 2GB DDR1, ATI Radeon X1900XTX.

Anyone have any ideas on how to sort this out? As as much as I want to I can't afford the new PC at the moment :(

Oh and just to make things worse I have no spare components, that is to say no PCI-E Graphics cards or anything to swap with.

Thanks for any help!
Jcb33.
 
No onboard video on the mobo then?

It could be a number of things. Can you test your card in a mates computer? I would also test the psu, if those are fine then it's most likely the mobo.

Seeing as the system wont post we cant run software diagnostics you can only test components by switching them out.
 
It's not fun "guessing" when you have to pay for the parts to test it ;)

My guess would be the mobo but hopefully im wrong. If I had no parts to test, I would remove the GPU completely and try to boot the system.It should power on and then provide a series of beeps to say there is no video.

If the system can post (power on self test) without the GPU then it's a 50/50 between the GPU being dead or the PSU isn't giving enough juice to power the GPU and the rest of the system. If I recall the PCI-EX slot will draw 75 watts alone not including any additional power cables you have attached to the GPU.

Hopefully I've given you enough toget started, post back what you find as you go
 
honosuseri said:
It's not fun "guessing" when you have to pay for the parts to test it ;)

My guess would be the mobo but hopefully im wrong. If I had no parts to test, I would remove the GPU completely and try to boot the system.It should power on and then provide a series of beeps to say there is no video.

If the system can post (power on self test) without the GPU then it's a 50/50 between the GPU being dead or the PSU isn't giving enough juice to power the GPU and the rest of the system. If I recall the PCI-EX slot will draw 75 watts alone not including any additional power cables you have attached to the GPU.

Hopefully I've given you enough toget started, post back what you find as you go
Click to expand...

Hypocrite :eek:
 
Underlining what I've said doesn't change the meaning of what I said.

Your post is a guess at it being the GFX, which is logical however if he buys a new GFX card on your suggestion and it's not the fault the OP may not be amused.

That's why I posted showing how he could confirm your guess without paying for a replacement. That's assuming he can't test or borrow parts on a working rig. Me being helpful i'd agree with......... Hyprocrite not so much ;)
 
Ok, I have tried:

Reseating the CPU, PSU Connections, RAM, and Graphics Card with no luck.

Removing the Graphics Card + Power Connector, still the same, fans and lights but no beeps

Also resetting the CMOS with no joy.... This is not looking good for my poor PC :(

Anyone have any idea what would cause it to go from browsing a webpage to dead with no warning signs?

Jcb33.
 
Well it's possible that GPU is still ok. The mobo should beep without the GFX, you still need to test the PSU but it's looking more likely that it is the mobo. I'd hate to have my guess proved right :(

You did say the machine was old so it's wear and tear more than anything you have done specifically.
 
honosuseri said:
Well it's possible that GPU is still ok. The mobo should beep without the GFX, you still need to test the PSU but it's looking more likely that it is the mobo. I'd hate to have my guess proved right :(

You did say the machine was old so it's wear and tear more than anything you have done specifically.
Click to expand...

I do not have a spare PSU to test it with which is a pain... But as you said no beeps looks like it could well be the Motherboard :(

It is 5 and a half years old, but I would have hoped it would keep going having never been overclocked etc.... To just give up the ghost while browsing the net.... Well that is just sad :(

I may have to invest in a new PC afterall.... Though this is not the best time to be doing so.... I have a spec for a new PC though no idea on what PSU's are good at the moment as I did intend on reusing my current one.

Jcb33.
 
Look for shorts between the motherboard and case, both around the mounting holes (install insulator washers as needed, top or bottom) and at the corners. If the motherboard isn't supported withn about 1" - 2" of a corner, it's possible for it and the case to flex enough to make them short together, and adding a rubber or plastic stick-on bumper to the case there will prevent shorts.

Because your PSU turns on, its +5Vstandby supply is working, and because the fans are spinning full blast, the +12V is probably OK. Also a spinning hard drive means the +12V and +5.0V are within 5-10% of what they should be. That leaves the +3.3V in question, and I don't know how to test that without a meter, but even the cheapest digital 3.5 digit meter is highly accurate and much better than a PSU tester that does not have a digital numeric readout. Testers that have nothing but lights can pass a PSU even if the voltages are way too low to turn on the computer. If you can't test your PSU, you really need to borrow a known good one to test your motherboard.

Bad electrolytic capacitors can make PSUs, motherboards, and graphics adapters fail, and some brands, almost all of them non-Japanese, often fail in 3-5 years. Caps that are bulging or leaking have definitely failed, but caps that look fine on the outside can also be rotten inside. Also high power CPUs (Pentium 4) or graphics cards can make even good caps go bad in 5 years. BadCaps.net has a lot of information about capacitor-related problems.
 
Check for +5 volts on the 20/24 pin Gray cable, if the +5volts is not present it is most probably a psu problem (you need a multimeter for this or a psu tester but a cheap multimeter can be had for a fiver).
This Gray cable tells the motherboard that all is ok on the PSU side and it is ok to power up.
The system fans and the Graphics card fans work cause the motherboard has send the power good signal to the PSU (via the green cable) and there is power to the +12v, +5v, +3.3v etc.

If there is no +5volts on the gray cable and your handy in disassembling things try to open your psu up maybe you can get lucky and it is just a leaking capacitor which can be replaced for a few quid.
Note: High voltages are present inside the psu so be carefull if you decide to open it up.
 
You can google for the pinouts of atx PSUs. I think it's pins 14&15 you short with a paperclip etc which will act as an on switch (turn power on/off at the wall) then you could use a multimeter to check your voltages as some of the other guys have mentioned......ideally it's much easier to swap it out for a known good psu.

What wattage and brand is the current PSU?

If your answer is *insert generic brand name* 20pin connector and 300-400W it would be wise to upgrade the PSU now. It's not going to cut it for a mobo bundle upgrade. You are intitled to free delivery so you won't be penalised for making individual purchases for parts.

The PSU you buy will largely depend on what you think you might upgrade the system to in the future. If your not bothered about SLI or Xfire the Lepa N series 600W PSU is £40ish a good budget PSU if you are on a tight budget.

Worst case scenario it's not the PSU that was faulty, then we are talking a new mobo bundle, possibly HDDs and DVD drives too if you are using IDE at the mo.

Post back what you find out about your PSU and we can discuss your options further then.
 
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