RMAed GA-MA78GM-S2H: no post, no beep

My computer stopped posting some months ago. No beeps when I removed RAM: tried different RAM combos, and unplugged everything.

I RMAed the motherboard. It was sent back with no information about the repair. I tested it, and it didn't work.

I tested the powersupply on another computer, and it works. I suspected it was the PSU because the keyboard lights don't turn on, but it does work and the fans do power on.

I have tried to isolate shortages by laying it out on the box (from screws, pins, etc), without luck.

Does anyone have any other ideas besides RMAing the CPU? Is it possible it is still broken after an RMA, or should I look elsewhere?

GIGABYTE GA-MA78GM-S2H
Crucial Ballistix 2GB 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400)
Antec Sonata III 500 ATX Mid Tower Computer Case 500W Power Supply

Thanks very very much for any ideas. I've heard of clearing CMOS, but my board doesn't have a jumper on it, and I can't find one. Also: it worked fine for months, then just stopped one day. I have lost most of my hope that I can fix this.

Well, I did test its PSU on my other computer. The only thing is, I didn't check the separate 5v wire (4-pin), because the test motherboard doesn't use that.

Do you think that if the keyboard doesn't light, it's definitely the PSU: that it can't be the CPU? If so, it must just be the separate 4-pin that's dead, because I tested the 12v 24-pin wire. Thanks for your idea.

I am thinking now - that it's potentially the OUTLET, not the computer. I'll check that.

Additionally:

I just tested it.

• I used a different outlet/electric line
• I tried a PCI VGA
• I tried the two memory sticks in different slots and variations
• I removed the battery for a minute to clear the CMOS
• I listened for beeps.

Still no sign of response at all, except that the monitor detects it was plugged in (it turns off the self-test box). Can I conclusively say that it is the CPU, now? Thanks again.

Hello
I have the same problem in one of the two GA-MA78GM-S2H rev 1.1 MB's at F5 bios I have:
One is functioning fine 24/7 for 5 months now (MDT 4GB ram, AMD X2 4850E). This is my server

The hardware of the other PC is a little different:
Kingston 2GB ram (listed in the compatibility list of Gigabyte), AMD X3 8450
The PC functioned for about 2 weeks without any problems and hung at once and after that no post, no video.
Discs spin up, Ethernet light is on but the rest. Nothing.
RMA'ed and got a new board a few weeks later. Again rev 1.1

The board worked fine for again a about 2 weeks (tested with high cpu load and CPU temp never was higher than about 40°C at 100% CPU load) but yesterday the same thing happened! During video rendering it just stopped again. No post, no video
Both PC's are not overclocked.

I'm wondering if I'm doing something wrong?
Did the following today:
- removed power and removed battery for a few minutes: no change
- Removed one RAM block, no change
- Disconnected DVD player and all harddisks, no change
- I can't change bios settings as I have no video output

I don't like to exchange components with my server as it will be offline then...but maybe I will have to do that in the end..
Any suggestions to test? before RMA it again (it took 3 weeks last time!).

Thanks!
Willem