Sorry if I'm not doing this right, but I started a thread (CLICK HERE), got some good replies and the thread got closed as "solved", but now it turns out it's not. I tried to post a reply but was not allowed to (in fact I lost the reply I typed - ouch). So I'm re-opening it by posting it again - follow the link to get the background...
I bought and installed a new CMOS battery, but I still get no POST screen (and no case speaker beep) from the mobo when I try to boot from my computer with the ECS Elitegroup K7S5A motherboard. In addition to what I typed in the original thread, I've now tried:
disconnecting everything except AGP graphics card, PSU and CPU/fan
replacing the PSU with a 450W Thermaltake PSU
moving the CMOS reset jumper back and forth
removing all metal screws and fiddling with the mobo to look for short-circuits
I have not yet replaced the case speaker or removed the mobo from the case. Those are the only things I can think of to try next, but they seem like some amount of pain for a motherboard that's not worth all that much.
Any other ideas of things I could try?
thanks to alyoshka for the replies so far, and to anyone else who might reply in the future.
Does your AGP have a FAN on the heatsink or is it a Fanless one?
If it has the Fan on it , do you see it move when you power on the rig?
If that happens then your card is getting the power it needs.... so the problem lies somewhere else....
If you can get a bottle of Iso propyle, (any Chemist) get one, use a swab of soft cloth dipped in it and clean the whole Mobo, use a soft brush dipped in IP for the slots and pins....
Wait for it to dryout then just plug in the processor and the AGP outside the case not in it.
Connect the PSU and use a screwdriver to short the start button pins to start it up....
see if you get a boot screen after that...
Breadboard with just motherboard, CPU & HSF, case speaker, and PSU. You do have a case speaker installed, right? If not, you really, really need one. If your case or motherboard didn't come with a system speaker, you can buy one here: http://www.cwc-group.com/casp.html
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.
Motherboard LED's mean very little. When on, all they are telling you is that the computer os plugged into a live power socket and the PSU is switched.
Remember, at this time, you do not have a graphics card installed so the load on your PSU will be reduced.
If no beeps:
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.
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 or long single beeps indicate a problem with the memory.
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.
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.
I'm working through the troubleshooting guide, and I'll pick up a bottle of iso alcohol (plus maybe a bottle of drinking alcohol for myself) later today.
One question keeps coming up for me - I'm never getting beeps from the case speaker, even with no memory installed, no CPU installed, etc. I've double-checked that the case/speaker I'm using works, and I've used the two PSU's I'm testing in other systems, and they seem to work.
Wouldn't it be normal to hear some sort of beep codes when the system starts up if the CPU is missing or fried, or if there's no video card, or no memory, etc?
I now have the board out of the case and sitting on a foam pad, so I know it's not shorting with the case.
I'm really starting to think this board is just junk, but now I've spent so much time on it that I'm getting stubborn.
It's normal to get beep codes in the old mobos.... if they have a small buzzer kind of speaker attached on the board itself. But in the new mobos and some old ones the onboard buzzer is not there, so the have a set of pins on the board to connect to the case speaker or a buzzer that is usually provided by either the case manufacturer or the mobo manufacturer.
If you feel, there could also be a mistake in connecting the pins of the speaker to the mobo, since the pins are usually 1 place apart....
it's like three pin set with one center pin missing just above the FP power button pin....
Check again to see if you've connected the speaker correctly....
Yeah, this board definitely has pins that attach to the case speaker. I made sure that the case speaker is working (by messing around with an even older board that I got to work today - it had identical pins for the speaker cable as the K7s5A), so I'm pretty confident that no signal is passing from the board into the speaker wire at any point. Of course that doesn't really define the problem - it's possible that the bloody speaker pins on the mobo are malfunctioning for all I know. I failed to get some iso alcohol today - that seemed like a good suggestion. I'll try that soon.
So just to confirm for my sanity ... I'm correct in thinking that on a working board with a working case speaker attached, it definitely would output some beep codes when I try to power the system on with no memory, or no video card, or no CPU installed, right?
At this point I will consider it a major victory if I can just get the damn thing to beep at me.
Well, I think I'm at the end of the line. I wiped it down with iso alcohol, ran through (almost) all of the steps in the troubleshooting checklist, and I'm already basically breadboarding it. I even found another speaker to plug in, but I still can't get any beeps no matter what's plugged in (or not) to the board, and obviously no video/post.
To top it all off, I looked on craigslist and someone is selling a vastly superior mobo in my neighborhood for $40 - seems like an omen.
Thanks to everyone who chipped in to help in my silly quest to salvage an old relic. (In this campaign I've gotten two even older boards/CPU's working again with stripped down WindowsXP installs, plus now I have a spare new CMOS battery and some iso alcohol in the house, so it hasn't been a total loss!)