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New build, no signal

Last response: in Systems
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January 6, 2012 8:57:03 PM

I'll post the specs first:

Case
Mainboard
Video
CPU
RAM
HDD
PSU


Now, on to the problem. This is a build my friend put together, and he's rather a novice PC builder at the moment. He currently live in Utah, so I am unable to go and troubleshoot the system for him, but have been guiding him over the phone. The problem is that currently, the monitor receives no signal. Here is the breakdown of what has been done and the problems faced along the way.

First my friend did the rookie mistake of putting every sing part inside the system before ever booting it. At this point he got a beep code of three long beeps continuous. I assumed this meant it was memory, and had him remove all of the sticks and try them in slot A1 individually. All sticks provided the same beep code.

Now, thinking it could be a number of things causing this my first suspicion was the motherboard. But before anything else I had him make sure the RAM was seated well, and had him check all of his connections. He said evenything checked out so I told him I suspected the motherboard. He decided to try a CMOS reset which I figured couldn't hurt. Nothing happened. I advised him to make sure his PSU was unplugged and to try the CMOS again, this time the computer started but the monitor showed no signal.

Now, realizing this could still be a number of things I ran him down the Tom's checklist (except for bread boarding as he still refuses to try it). The CPU power connector was inserted properly, he said he made sure the standoffs were all inserted properly, and we just went down the list until I got him convinced to remove everything except for the CPU/HSF, mobo, and PSU. At this point he got the same three continuous beeps that he got before. I had him insert one RAM stick, and he got 1 long 8 short beeps.

After a quick google I saw this meant his video was not being detected, this was good as he did not have his video card inserted. I had him put it in, and he started receiving just 8 short beeps no long beep. I looked it up and saw it meant the video card was not working properly.

And that is the point we are at now. No signal, and 8 short beeps. Is it his video card for certain? I'm not so sure.

More about : build signal

January 7, 2012 1:15:37 AM

Does the friend have access to some other video card? One that he can borrow from someone friends/family?

Talk him into breadboarding, it is a routine troubleshooting step and he should get used to doing it, even if it likely won't help him in this case.

Also, RAM is one of the biggest causes of problems with new computers. You did well by having him try each stick in slot 1. You may want to have him try to leave the video card in and instead put each of the sticks of RAM individually into all the other motherboard slots too.

It would also be nice if you could have him run Memtest86+ while he is sleeping tonight.
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January 7, 2012 2:02:10 AM

Easy enough to check the video card. Just plug it into your computer.

I think it is time to breadbord.

The following is an expansion of my troubleshooting tips in the breadboarding link in the "Cannot boot" thread.
http://www.tomshardware.com/forum/261145-31-read-postin...

I have tested the following beep patterns on Gigabyte, eVGA, and ECS motherboards. Other BIOS' may be different, but they all use a single short beep for a successful POST.

Breadboard - that will help isolate any kind of case problem you might have.
http://www.tomshardware.com/forum/262730-31-breadboardi...

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 (standby power supply): 5 volts always on. The green wire should also have 5 volts on it. It should go to 0 volts when you press the case power button (this is also a good way to test the power switch and the associated wiring), then back to 5 volts when you release the case power switch. 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.
http://www.youtube.com/watch?v=5FWXgQSokF4&feature=yout...

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.

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January 7, 2012 2:14:24 AM

Unfortunately he does not have any extra working hardware to try and diagnose with. The parts he ordered is all he has to work with.

I think at this point I'll just have to convince him to bread board it. He's afraid that he'll damage his hardware by doing that. But he's tried everything else he can, so that's a logical next step. Thanks for the suggestions, I'll post back if/when we get some new results.
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January 7, 2012 11:33:29 AM

How did he get everything in the PC if he is scared he will damage his hardware by breadboarding?
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January 7, 2012 1:23:48 PM

A mistake novice builder's commonly make is improperly mounting the board into the case, causing a direct short. There is no other choice at this point if he wants to continue troubleshooting except by undoing everything he has done, and trying to start the board out of the case. Have him come here and read this thread, he won't hurt anything as long as the board is on a non conductive surface like a wooden table top, or a nice big flat piece of cardboard.
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January 9, 2012 12:52:50 AM

Raiddinn said:
How did he get everything in the PC if he is scared he will damage his hardware by breadboarding?


Haha, he seems to think he will either create a short or expose it to too much static electricity if he lets the parts run outside of a case. I've convince him otherwise now, so he has finally bread boarded his parts. Bread boarding yielded the same results, 8 short beeps and no signal. Any ideas?
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January 9, 2012 4:47:42 AM

Does he have a different video card laying around somewhere, or one he can borrow from somewhere/someone?
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January 10, 2012 5:56:52 PM

Afraid not, only components he has are the ones he just bought.
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January 10, 2012 11:34:39 PM

If he can't source one from somewhere, have him look into RMAing the card.
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!