Author Topic: Computer "boots" without video (Read 20606 times)

DanTheTechMan · « **on:** December 31, 2014, 04:48:48 pm »

I am fixing a computer for a friend, and ran into a very interesting scenario. The computer boots (or acts as such; all lights come on, fan spinning NORMALLY, not excessively loudly, even the optical drive shows activity as it should). But, as the title suggests, I never get any video. No BIOS screen (I won't get any further than that because I just installed a unformatted hard drive in the machine). I even tried Installing a PCI video card to see if the onboard video was having issues (as rare as that is, I know it CAN happen), without any luck. All out of ideas, and almost out of options, I am reaching out to the cyberworld for help.

For the record, the computer I'm fixing is an HP Pavilion Slimline S3321P.

jraju · « **Reply #1 on:** January 01, 2015, 01:33:48 am »

Hi, What do you mean by unformated hard disc. Hard disc is a storage device.
Did you install the OS. There was no mention of it.
If the problem is one of installed OS, then no sign of BIOs and only sound running is a defect with Hard disc. Master Boot record either becomes corrupt. Try by safe mode booting F8, and then select command prompt, and then type fixmbr. It may fix the problem if it is only hard disc failture.
Some more information is required to give particular solution

DanTheTechMan · « **Reply #2 on:** January 01, 2015, 05:41:21 am »

By "unformatted" hard drive, I mean exactly what I say: not formatted, blank, NO OS. I ordered it, received it , installed it. After about 2-3 hours of struggling to get the damn machine to even power on, I succeeded at that, but without any video output. Now, in this case, I should be presented with the BIOS screen first, then the Windows installation should start to load. However, IF this IS happening, I can't see it happening. Please help.

Boggin · « **Reply #3 on:** January 01, 2015, 07:50:40 am »

Can you get into the BIOS to see if the HDD is recognized or will the machine boot up into the BIOS with the HDD removed - some machines can and cannot do this.

In the BIOS you may have an option to enable VGA but see if this tutorial helps http://pcsupport.about.com/od/operatingsystems/ss/windows-7-new-install-part-1.htm

DanTheTechMan · « **Reply #4 on:** January 01, 2015, 12:17:16 pm »

I don't get any video at all, not even the BIOS displays. So, what you suggested will not work. Is there any other way I can get the video output to work (preferably outputted to the PCI card)?

Boggin · « **Reply #5 on:** January 01, 2015, 03:44:09 pm »

Is there a VGA port that you can plug the monitor into ?

DanTheTechMan · « **Reply #6 on:** January 01, 2015, 04:06:19 pm »

Yes, onboard and external (PCI), both of which display nothing.

jraju · « **Reply #7 on:** January 02, 2015, 01:07:27 am »

Hi, Dan is the monitor working first. If it does not , then you have to check the monitor. The computer may be working because of noted sounds, but if monitor is not working, then you do not see anything on monitor. Check the monitor. Pl see the self test link:
http://skp.samsungcsportal.com/integrated/popup/FaqDetailPopupMobile.jsp?cdsite=africa_en&seq=265291
If it is working, then there is problem in your video card that connects to the computer

DanTheTechMan · « **Reply #8 on:** January 02, 2015, 04:58:11 pm »

Monitor works. As I keep stating, I have no video output. How do I fix the PC as to regain video output? Bear in mind this is for a friend of mine, as I mentioned in the initial post.

Shane · « **Reply #9 on:** January 02, 2015, 06:10:42 pm »

To rule out a bad mother board or bad CPU this is a little trick that I do when I get a system with no boot screen. Pull the memory out of the motherboard. Then turn it on.

The motherboard should beep at you, normally a beep error code. Which of course would be the fact that there is no memory installed. When it does beep I know the motherboard and cpu and working at least to that point.

When i dont get ANY beeps, then I know it is either the cpu or motherboard (Both are needed to make the beeps)

If you get no beeps then the first thing to do is to try a different power supply to make sure that it isnt a simple problem of not enough juice coming through. Also do a power drain if you have done so yet as well as that is the only true way to reset hardware.

let me know how that goes

Shane

DanTheTechMan · « **Reply #10 on:** January 02, 2015, 06:46:02 pm »

Didn't think of that, thanks Shane! BTW, I already swapped out CPUs, so that wasn't an issue. Power supply is aftermarket, so that could be an issue. Motherboard is the most likely culprit, though (I'm in over my head, but hey, big payday when this is all said and done!). I still have the original power supply, but replaced it because it would get really hot really fast, put this new power supply seems to do the same thing. Should I try the original power supply (it handles less power, but I've added more to the PC since)? Finally, some progress! Thanks again, Shane!

Shane · « **Reply #11 on:** January 02, 2015, 06:58:34 pm »

If the old power supply works then you can test with it. You simply want to test with a known good power supply

Shane

Boggin · « **Reply #12 on:** January 03, 2015, 02:20:20 am »

If both PSUs get hot really fast then that would suggest a high resistance somewhere.

Open the computer up and look for capacitor cans with swollen tops or any other sign of overheating on the resistors etc.

DanTheTechMan · « **Reply #13 on:** January 03, 2015, 04:58:51 am »

Thanks Boggin, looks like I'm on the hunt for a replacement motherboard for his PC, and considering the type (HP Pavilion Slimline), I don't think it will be easy to find or install.

Boggin · « **Reply #14 on:** January 03, 2015, 05:55:11 am »

Quote from: DanTheTechMan on January 03, 2015, 04:58:51 am

Thanks Boggin, looks like I'm on the hunt for a replacement motherboard his PC, and considering the type (HP Pavilion Slimline), I don't think it will be easy to find or install.

ebay seem to have a few but you may need to Google for the exact model http://www.ebay.com/bhp/hp-pavilion-slimline-motherboard

Came across this 2 year old article which if applies, could explain why the board has gone down http://www.computerworld.com/article/2505019/windows-pcs/hp-reports--higher-than-expected--failures-of-some-desktop-pc-motherboards.html

DanTheTechMan · « **Reply #15 on:** January 03, 2015, 07:23:49 am »

Thanks again Boggin, will look into it. Should I buy a new PSU as well, considering the amount of stress the current one has been under?

Boggin · « **Reply #16 on:** January 03, 2015, 03:44:24 pm »

I think I would wait and see how they perform with a new motherboard as the older of the two could still be serviceable, as the newer one was exhibiting the same symptoms and could have been related to the condition of the MB.

If you've found any defective components on the MB and you are handy with a soldering iron, then a repair could be possible.

Shane · « **Reply #17 on:** January 05, 2015, 09:24:59 pm »

Did the system have trouble with the other power supply as well?

Shane

jraju · « **Reply #18 on:** January 05, 2015, 09:33:13 pm »

Hi, The thread owner has replaced three mother boards and still have the same black screen with no signs. How you say the monitor is working, just because of continuous green light? Could not be there an error in monitor. The system making sounds denotes that there is some inside activity. probably mother board is working. But if the problem persists even with replacing the MB, then the problem appears to be weird.
Shane , could it not be monitor.

Shane · « **Reply #19 on:** January 05, 2015, 09:57:55 pm »

Hard to tell, I also had a system once doing the same thing, the problem? A damn screw had fallen behind the board and was shorting it out lol

Shane