I am not sure this is an appropriate place to bring my motherboard troubles, but I am trying to make a new MythTV computer with an Asus M2NPV-VM, Socket AM2 DDR motherboard. I got this particularly motherboard because documentation I read led me to believe this hardware was very thoroughly supported by MythTV.

I am having the weird trouble getting the system started. I have no idea where the problem is coming from. I bought a nice Enermax 350 Watt power supply, and hooked it up, but the computer refuses to turn on. Nothing. It does not turn on, no lights, no fans spin up. It is as if the computer is not even plugged in.

I would have thought the power supply was dead, but there is a single small green light that illuminates on the motherboard itself, indicating that it senses there is power attached and ready. I have tried 4 different power supplies, 1 of which I can verify is just fine (I am using it now). None of the different power supplies got the system to start up, but there were some odd results.

For some of the power supplies, the motherboard has a 24-pin power connector. If I only connect 20 of the connectors (not connecting the extra 4 pin connector), it sometimes will spin up the fans, but this behavior is not the same for each power supply.

Online manual(s) here:
Manuals

Direct link to the PDF manual
PDF file

I have been trying for weeks to get this motherboard to work and I just have no idea what is going on. The CPU fan is plugged into the motherboard properly, though I suppose that might still cause problems. The motherboard plug is a 4 pin connector, while the cord from the CPU fan is only 3 pins. But that should not stop it from spinning up on some power supplies, and not spinning on others.

The case buttons are hooked up properly (I have verified this several times with the manual).

Any help would be appreciated.

As well as plugging in (all of) the 24pin ATX power connector (EATXPWR), you are plugging into the auxiliary 12V connector (ATX12V) from the PSU?
Have you checked that your PSU is rated for the board and CPU?
Have you checked that after being inserted into the case, that there is nothing fouling the underside of the board and the power plugs are pushed fully home?

Bruce S.

_________________
Updated 2019/10/26: AthlonII X2 265 Gigabyte GA-970A-DS3P
16Gb PC 1866 DDR3, 500GB+2TB+4TB SATA HDD,
SATA DVD-RW Asus DRW-24D5MT , NVIDIA GeForce GT1080
Hauppauage Nova-T 500, Nova-T LinHes R8.6.1

I have 3 of these boards working with various power supplies without trouble. You need a 20+4 or 24 pin main connection and as bruce_s01 mentioned the additional 4-pin 12V connector.

If you have tried that already, I would recommend removing everything from the board except power, CPU and memory and start it up. At the very least, with a known good PSU, your CPU fan should spin up.

You could also try resetting the CMOS in case something is really fouled up there.

(Insert normal troubleshooting stuff here: Swap CPU, swap memory, etc.)

Neither Bruce or Slow mentioned it, but there's an LED on the mobo between the PCI slots that will light up when there's standby power available.

If that LED isn't lit, and the PS is swited on, there's probably a short somewhere. Take the mobo out of the case, and sit it on a piece of cardboard...then wire it up and see if it fires up.

I've used both 20 and 24 pin PSU's on this board and they both worked fine.

Thanks everyone for replying. I appreciate the help.

I have tried removing all components from the system, and use only CPU, RAM, Mobo, using the on-board video, and PSU. The results are the same as I mentioned above.

@bruce_s01: Yes, I have tried plugging in the auxiliary 12v connector from the PSU each time. Actually, when I leave it uplugged I am can get the fans to spin up on certain power supplies, but not all of them like I mentioned before.

@slowtolearn: I will try resetting the CMOS when I get a chance.

@larrybpsu: the LED on the motherboard has lit up each time with each PSU I have tried.

Has this board ever worked for you? I know it's picky about the RAM voltage (requires 1.8 or 1.9, IIRC) What memory (make, model and voltage) do you have in there?

And which AM2 CPU are you using?

One other question about the pilot-light, as I'll call it....

Ok, so it light's up when you have the PS connected, and switched on.

When you attempt to power up the board, does the light stay the same, get brighter, or does it dim out? If it doesn't dim out, then I'd rule out the short.

It could be a bad mobo.

The memory voltage issue IS important, and I selected memory from Newegg that others here used. Bought the board and memory at the same time.

I tried removing the entire board from the case (in case the mounting was somehow causing a short).

I tried reseting the CMOS, but that did not help.

Processor:
AMD Athlon 64 X2 4200+(65W) Windsor 2.2GHz Socket AM2 Processor Model ADO4200CUBOX - Retail

Ram:
CORSAIR XMS2 512MB 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Desktop Memory - Retail

I do not know what to say about the voltage. I do not really understand what I should be looking for.

EDIT: Updated Ram, original listing was incorrect

Don't AM2 CPU / mobos require DDR2?

You may be right. I had listed the incorrect ram on my prior post. The ram I was using in this system is this:

CORSAIR XMS2 512MB 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Desktop Memory - Retail
(http://www.newegg.com/Product/Product.a ... 6820145567)

"Voltage 2.1V"

The M2NPV-VM boards are apparently very picky about the memory voltage. I have used the following in mine:
http://www.newegg.com/Product/Product.a ... 6820220066
http://www.newegg.com/Product/Product.a ... 6820231098

Again, has this board ever worked for you? If it has, and you're using the same memory it had when it was working, then you can probably rule that out...