Homebuilt desktop not booting, help needed

So the other day, the desktop I built wouldn't boot. I have a Windows XP installation CD that I'm using to try to help. I went and did some tests and here's what I have figured out:

I can load the BIOS. The BIOS seems fine.
There's some sort of POST startup failure, indicated by the sounds. I don't know the codes, and I've gotten different failures, indicated by different beep sequences. Now I don't get any sound from it, which is odd.

I put in the CD and tried to boot from the CD. It fails to boot from the CD, it just loops after it fails to boot.

The HD won't boot. When I try to boot the HD, it fails. It hangs on the HD and will stay there for hours.

The HD wouldn't boot in another desktop, as I tried. It hangs just the same way.

A working HD in another desktop won't boot on this desktop. I get all sorts of errors trying to boot it. It's running Vista and when I boot it, it goes crazy telling me to run system restore and loops that, it restarts if I try to start normally. This HD is working, I've tried it since and it boots fine.

The HD can be accessed when used as an external drive, I took ownership of the drive in Windows 7 and can access all the files

So what's wrong? Motherboard? HD? I'm not quite sure, it seems like both to me to be honest. Ideas? I could buy a new HD+mobo for like 150 or so, it's not expensive, I just don't want to have to take everything out of the case and all, I'm lazy. I'd do it if I need to though, I just would rather be sure of what's the problem before I do anything.

Alternatively, a new machine with i3, 4GB RAM, 1TB is only 450 or so, it's not too expensive. I'm running a Q6600 in that one, I've seen the i3 530 benchmarks as being better than the Q6600. Though, the price is a considerable difference.
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  1. HDD from another machine has drivers for a different mobo! Are you talking about the original drive being accessible as an external drive?
  2. darksteel said:

    ... I just don't want to have to take everything out of the case and all, I'm lazy.

    Unfortunately, that's one of the best troubleshooting techniques around. You have easier access to the parts and it removes one of the possible problems with a new build - case grounding problems.

    Work systematically through our standard checklist and troubleshooting thread:
    I mean work through, not just read over it. We spent a lot of time on this. It should find most of the problems.

    If not, continue.

    I have tested the following beep patterns on Gigabyte, eVGA, and ECS motherboards. Other BIOS' may be different.

    Breadboard - that will help isolate any kind of case problem you might have.

    Breadboard with just motherboard, CPU & HSF, case speaker, and PSU.

    Make sure you plug the CPU power cable in. The system will not boot without it.

    I always breadboard a new build. It takes only a few minutes, and you know you are putting good parts in the case once you are finished.

    You can turn on the PC by momentarily shorting the two pins that the case power switch goes to. You should hear a series of long, single beeps indicating memory problems. Silence indicates a problem with (in most likely order) the PSU, motherboard, or CPU. Remember, at this time, you do not have a graphics card installed so the load on your PSU will be reduced.

    If no beeps:
    Running fans and drives and motherboard LED's do not necessarily indicate a good PSU. In the absence of a single short beep, they also do not indicate that the system is booting.

    At this point, you can sort of check the PSU. Try to borrow a known good PSU of around 550 - 600 watts. That will power just about any system with a single GPU. If you cannot do that, use a DMM to measure the voltages. Measure between the colored wires and either chassis ground or the black wires. Yellow wires should be 12 volts. Red wires: +5 volts, orange wires: +3.3 volts, blue wire : -12 volts, violet wire: 5 volts always on. Tolerances are +/- 5% except for the -12 volts which is +/- 10%.

    The gray wire is really important. It should go from 0 to +5 volts when you turn the PSU on with the case switch. CPU needs this signal to boot.

    You can turn on the PSU by completely disconnecting the PSU and using a paperclip or jumper wire to short the green wire to one of the neighboring black wires.

    A way that might be easier is to use the main power plug. Working from the back of the plug where the wires come out, use a bare paperclip to short between the green wire and one of the neighboring black wires. That will do the same thing with an installed PSU. It is also an easy way to bypass a questionable case power switch.

    This checks the PSU under no load conditions, so it is not completely reliable. But if it can not pass this, it is dead. Then repeat the checks with the PSU plugged into the computer to put a load on the PSU.

    If the system beeps:
    If it looks like the PSU is good, install a memory stick. Boot. Beep pattern should change to one long and several short beeps indicating a missing graphics card.

    Silence, long single beeps, or series of short beeps indicate a problem with the memory. If you get short beeps verify that the memory is in the appropriate motherboard slots.

    Insert the video card and connect any necessary PCIe power connectors. Boot. At this point, the system should POST successfully (a single short beep). Notice that you do not need keyboard, mouse, monitor, or drives to successfully POST.
    At this point, if the system doesn't work, it's either the video card or an inadequate PSU. Or rarely - the motherboard's PCIe interface.

    Now start connecting the rest of the devices starting with the monitor, then keyboard and mouse, then the rest of the devices, testing after each step. It's possible that you can pass the POST with a defective video card. The POST routines can only check the video interface. It cannot check the internal parts of the video card.
  3. I did a bit of a breadboard check. The system does the normal without anything, looking for something to boot. With the CD drive, same. With the memory/GPU, same. With the HD, it hangs. The motherboard has integrated graphics which I tried, didn't change the results

    So as far as I can tell, things seem to work fine without a drive it can successfully try to boot, but once I try with the drive, it either loops a restart or hangs.

    I wiped the drive after I backed it off. I did a quick format with computer management on Windows 7 to clean it. When I have it connected and try to load the OS installation disc, it doesn't do anything different than before.

    I tried to use the WD program to check if the drive was fine or not, and it is unable to find the license it needs, suggesting they're not in the same path. I looked at the burned image, all the files, including the one it cannot find, are on the root of the disc, so I don't know what's going on with that program.

    The only thing I can think is the problem at this point is the HD. I'm planning to grab a Caviar Green 1.5TB for 60 bucks tomorrow, not a bad price (half of what I paid for it a year ago). If it works, good, if not, we got more testing to do. If anything, I can and would, use it as a backup, and I almost bought one this Christmas actually, so it definitely won't go to waste if it doesn't solve my issue.
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