POST Diagnostics Cards

[BobH]

My desktop PC is still not functioning. I've checked my PSU (Corsair 750W), replaced my power on switch, replaced the mobo battery (C2032 3.0V), re-seated all the RAM modules, checked and re-seated power supply cables to the SSHD and both internal HDDs and the DVD drive as well as checking to be sure that all data cables are well seated in their proper mobo positions. I've also checked and rechecked all fan, LED, and power on cable connections. I've done everything suggested by the mobo manufacturer (ECS, Elite Z77H2-A3) in the troubleshooting section EXCEPT clearing CMOS (ie, resetting the BIOS).

Before resetting the BIOS, I've looked into testing the mobo. The only thing I've found that might do that is to install a POST test card. I've never done that but POST cards are cheap whereas mobos aren't.

Has anyone here ever used a POST card? If so, how did you go about choosing one, or are they all pretty much about the same? I'll need an IDE card for my mobo.

Suggestions for other diagnostic steps and recommendations for a POST card will be greatly appreciated and gratefully received.

[StuartR]

I can't answer the question, but I would like to know what actually happens when you power on the PC.

[viking33]

I can't answer the question, but I would like to know what actually happens when you power on the PC.

I second Stuart's suggestion, Bob. What does or doesn't happen at boot? LED'S. fan noise, HD activity. any pre-post beeps or what ever you can observe.
BTW, I've never used those POST cards, so can't say anything good or bad about them.

[BobH]

Hi Stuart!

Thanks for looking.

Nothing at all happens when I try to start the system. The fans don't come on. The LED ring around the power-on button doesn't light. There is no beeping. Nothing.

I'm afraid that I've shot myself in the foot at some point in trying to diagnose and fix the problem. The system failed to produce a video signal at first. Puzzled, I plugged the monitor into another PC and it came on. It also displayed its POST images when powered-on without connection to the PC.

When I opened the case (ATX), the first thing I did was to clean the inside of the case removing the dust. There wasn't really that much there, but cleaning is always the first step. I did it as I've always done it without being too aggressive. I then unplugged the 24-pin connector and the 4-pin 12V connector and tested each of the Molex and SATA power leads using a Corsair PSU tester. At first I got a flashing LL for the -12V reading but that was because I failed to connect any other load to the tester. I connected a 6-pin lead, and the LL went away and -12V was displayed. I proceeded then to test the Molex and SATA leads.

Not entirely confident of the tester, I then used a multi-meter to test the PSU, jumping the green wire with a ground (black) wire according to a web page article. I got spot on values or values well within the 10% tolerance. IIRC it was the 3.3V output that read 3.4V.

I then followed instructions to see if the system fans would come on with the jumper in place when the start button was pressed. They didn't, so I jumped the power-on connector on the mobo and the fans turned briefly then stopped. The article explained this away as a momentary switch that would not continuously apply power. I tried to test continuity on the power-on switch but got good results and bad results; so I ordered a new switch. Articles report that switch failure is often a problem. The new switch arrived today. I installed it being careful to get it on the right plugs on the mobo. The system still will not run the fans. I checked that the I/O switch on the PSU was in the I position and tried the new power-on switch several times with no success.

Clearing CMOS is a widely recommended step; however, before I opened the case for repair, I tried booting from a Win 7 DVD. The system would power on but never select the HDD for a read. Because the monitor would not display, I could not check BIOS settings by interrupting out to BIOS at boot time.

I'm at the end of my string as far as what next to do. PSU checks out; monitor checks out on another PC; power-on button has been replaced and is properly cabled on the mobo; RAM has been reseated; all leads have been checked for proper connection. The only think I've had no visibility into is the status of the mobo. That is why I'm considering a POST card to see what it will tell me. At this point, I don't know if the mobo is actually powered. There are no indicator lights that will tell me. The only LED light on the front of my case is the one on the new power button and it does not light.

ps: I forgot to mention that I even checked that I was getting AC current from the power cord. It checked at 124.5 V. US power is delivered at 110-120 VAC, 60 Hz. I don't have test equipment to test cycles, only voltage.

[StuartR]

I downloaded the user manual for that motherboard and read what they say about this issue.

a) System does not power up and the fans are not running.
1. Disassemble the PC to remove the VGA adaptor card, DDR memory, LAN, USB and other peripherals including keyboard and mouse. Leave only the motherboard, CPU with CPU cooler and power supply connected. Make sure the power cord is plugged into the wall socket & the switch on the Power Supply Unit (PSU) is turned “ on “ as well. Turn on again to see if the CPU and power supply fans are running.
2. Make sure to remove any unused screws or other metal objects such as screwdrivers from the inside PC case. This is to prevent damage from short circuit.
3. Check the CPU FAN connector is connected to the motherboard.
4. For Intel platforms check the pins on the CPU socket for damage or bent. A bent pin may cause failure to boot and sometimes permanent damage from short circuit.
5. Check the 12V power connector is connected to the motherboard.
6. Check that the 12V power & ATX connectors are fully inserted into the motherboard connectors. Make sure the latches of the cable and connector are locked into place.

Unusually this motherboard doesn't have any LEDs to help diagnose this kind of issue.

If you've tried everything on that list then I guess you might as well try clearing the CMOS.

[viking33]

I don't know, Bob. After a first read of your post, I suspect the PSU as the culprit. You say that a boot to a WIn DVD works but doesn't see the Drive? ( so there must be at least some voltages OK. )
Do you have a pin by pin list of the power outputs for your particular PSU?
Some have miltiple 12 and 5 volt outputs, so just one may be bad. Test of the power switch could have been to just momemtarily short the leads to get the results of the momentary that the switch itself would do.
Clearing the CMOS would probably be one of my last suspects but who knows?
So I have to do another read of your post but any other signs that you can provide would help.
At this point I suspect these items in order of probablility:
1, PSU
2. MOBO
3. OS itself
Hang in there, We will get it.

[BobH]

Thanks, Stuart!

I have tried everything on the ECS list of troubleshooting for this mobo except resetting CMOS. I'd like to know if the mobo is processing the power it should be receiving from the PSU as the latter has been bench checked and checked in situ and passed. Of course, if it is not, a POST test unit will not help at all.

Yes, I was surprised to find that the mobo has no lights to at least indicate that it is processing power much less display diagnostics as many mobos did in the past.

Again, thanks for your help!

[BobH]

Thanks, Viking Bob!

I might not have expressed myself correctly wrt the attempted boot. I could NOT get it to boot. I tried this before I opened the case and started trying to diagnose the problem. The disk would not power up an spin. Simultaneously, I could get no indication on the monitor that the system, ie, mobo, was signalling it; however, on powering off and on the monitor it flashed its POST signals and manufacturer (Asus) ID which led me to exonerate the monitor and point me toward components inside the case.

The first thing I did after cleaning away a bit of dust was to test the PSU. While my initial effort was amiss, the fault was mine, I think, in not placing a load on the tester. After reading web articles, I tried again and the PSU gave good readings.

One of the things I read was that he power-on switch in the case might have gone bad. The article suggested shorting the on/off switch pins on the mobo to see if the fans would spin. They did. The article also cautioned that the fans would spin only briefly due to the switch circuit being a momentary switch.

At this point, I don't suspect the OS. It resides on a SSHD. That, of course, doesn't mean that it cannot be corrupted; but I think it more likely that the mobo has failed.

I'm going to go back to ground zero today. I'll remove everything from the case, including the mobo and everything plugged into it. I'll retest the PSU to satisfy myself once again that it functions correctly. I'll got through the ECS troubleshooting suggestions again before reinstalling cards, etc.

Because I cannot see any sign that the mobo is processing power, I'll - as a last resort - clear CMOS; however, I don't expect that to do any good if the mobo is not passing power through circuits.

Looks like I'll be saving my pennies for another mobo.

Again, thanks for the help!

[viking33]

Reminds me of a few years ago, when BOTH the PSU AND MOBO failed!!!
It can happen! Probably the PSU was the inital problem and took out the MOBO on the way down. Hope that isn't your case.

[BobH]

The saga continues.

I've stripped the case except for 1 power fan that brings outside air into the case. Before I did so, I tried it again without success.

A visual inspection of the mobo shows no abnormalities - swollen components, etc. I have not yet removed the CPU because I don't have any di-electric grease on hand at the moment.

I HAVE checked the PSU again with the Corsair PSU Tester. This photo shows the results obtained today.

PSU Test 24 Mar.JPG

I will check it with the multi-tester tomorrow but do not expect any problems as I've been down this road once before.

At this point my guess is that the mobo is fried. I will reassemble it after bench testing the PSU completely with the multimeter. I think I might get a new case as this one is pretty old and newer ones have some additional cooling features.

Thanks to all for listening and offering suggestions.

[viking33]

The saga continues.

I've stripped the case except for 1 power fan that brings outside air into the case. Before I did so, I tried it again without success.

A visual inspection of the mobo shows no abnormalities - swollen components, etc. I have not yet removed the CPU because I don't have any di-electric grease on hand at the moment.

I HAVE checked the PSU again with the Corsair PSU Tester. This photo shows the results obtained today.

PSU Test 24 Mar.JPG

I will check it with the multi-tester tomorrow but do not expect any problems as I've been down this road once before.

At this point my guess is that the mobo is fried. I will reassemble it after bench testing the PSU completely with the multimeter. I think I might get a new case as this one is pretty old and newer ones have some additional cooling features.

Thanks to all for listening and offering suggestions.

Never used a meter such as the one you have but it does look like it's saying the PSU is OK. Have you checked ou this component comany down your way, called Directron? I've bought from them before with decent buys and you can pick and choose any and all components. Worth a look.

Directron