No post: is it the motherboard or the CPU

[rfrank44]

This is probably my eighth build and the first that has presented a significant problem. Here's the main component list:

MB = Gigabyte GA-M55SLI-S4
CPU = AMD|A64 X2 3800+
MEM = 1G x 2 of G. SKill F2-6400
PSU = Hiper 580W
Video card = ASUS EN7600GS 512M

--------------------------------

I know I have power to the motherboard because the CPU fan is running, but I'm getting no POST beeps and my monitor is not getting a signal from the video card. How do I isolate the problem if I need to RMA either the motherboard or the CPU? Am I correct in thinking that I should get POST beeps with just the CPU and cooler connected to the MB if everything is working properly? I went back to that point and then added the video card. Didn't add drives or keyboard but it seems that shouldn't matter if the board and CPU are functionaing properly. Am I right about that?

TIA for your help,
richard

 

[cutthroat]

Yeah, you should get POST beeps if either the CPU, memory, or video card is missing or bad. You did your troubleshooting well. Most likely the motherboard is bad.

Did you just build it, or is this an older machine? If you just built it are you triple sure you didn't miss anything important. I've built lots of machine too, and miss something from time to time.

I've built 5 of my own PC's, I got 3 DOA motherboards. :x That's against the odds, just unlucky I guess. Motherboards are the most RMA'd item though.

 

[rfrank44]

It's new. I'm just building it, and I was hoping to make quick work of the hardware because I have to move about 2 years of data and applications from another machine. That's the part I thought would take forever. Now it looks like this is going to slow everything down.

I don't know what I could have missed. When it didn't boot with the video card in place I stripped off everything and went back to a bare motherboard. I added the CPU and cooler and tried it. Nothing. Added memory. Nothing. Video card. No signal.

Thanks for the quick response. Looks like an RMA for me.

richard

 

[cutthroat]

Sounds like you got a DOA motherboard. After my previous experiences I always buy my motherboard close to home, that way if it's DOA I can just exchange it.

Good luck.

 

[CmdPT]

Did you plug in the 4 Pin correctly when I build my first computer I thought I plugged it in properly but I wasn't properly in the socket so only the CPU fan spin but no video and beeps whatsover try to see if plugged it in first.

 

[rfrank44]

The PSU has a 24 pin connector which is really a 20 and a 4 pin module. I pulled it and reset it just to make sure that it was in place.

I'm new here. You guys are good.

richard

 

[CmdPT]

Then yeah its probably a DOA Motherboard.

 

[burn-e86]

uh, this may sound stupid but make sure that you've checked all the pins to ensure that the speaker is hooked up in the right place...happened to me once when i was troubleshooting my build...turned out that the RAM wasnt inplace but i didnt get any beeps cause the speaker wasnt plugged in

 

[utaka95]

You will only get a POST beep with ram installed. If your BIOS is set to halt on all errors, not having a keyboard will stop it from booting. Hook up a keyboard, install a ram stick and try again. And your board may have another 4 pin plug besides the 24 pin plug - check again.

 

[Syntonic]

As the above poster was mentioning, start reseating everything as you might not have plugged in everything all the way or correctly before you RMA the motherboard. Beyond the 20+4 pin for your motherboard, there is the other 4pin 12v CPU connector which is between the rear IO panel and the CPU socket.

 

[rfrank44]

As the above poster was mentioning, start reseating everything as you might not have plugged in everything all the way or correctly before you RMA the motherboard. Beyond the 20+4 pin for your motherboard, there is the other 4pin 12v CPU connector which is between the rear IO panel and the CPU socket.

I was aware of the other four pin, but I was under the impression that I only needed to use it if the main PSU connector was a twenty pin. I just read the manual and it does say the 4 pin connector mainly supplies power to the CPU and the the system will not start without it. However, the extra 4 pin block on the 24 pin connector says "only for 24 pin ATX" Is anyone running a board with both the 24 pin and the 4 pin connectors plugged in? I was afraid of damaging the board by doing that.

Well, it's too late for this board. I already RMA'd it and packed it up for exchange. I might as well start fresh at this point.

Regarding the need to attach a keyboard, I thought Award BIOS would give one long beep and three short if the keyboard wasn't attached? Every few years I upgrade my PC. This round has involved more hardware changes than I can ever remember. A lot of old standards and procedures appear to be gone.

Well, I think the first thing I need is confirmation on connecting the power connectors. If I really needed the other four pin to power the CPU, that would certainly explain no POST beeps.

Thanks guys for your suggestions and help.

richard

 

[rfrank44]

I decided to unpack the motherboard and give it one last try with the extra power connector. What did I have to lose?

That did it!

Many thanks to all of you for you help and suggestions. Special thanks to the guys who pointed me in right direction regarding the extra power connector.

richard