Forgot where the pins go on a 648fx-a motherboard

Google search "P4M900-M4 motherboard wiring diagram" it should show you the pin outs.

Please provide further details. What happens when you press the power button? It does not automatically mean that your motherboard is failing.

if your computer came with a motherboard disc the sound drivers could be on it
click start control panel administrive tools computer management device manager scroll to sound,video and game controllers you might see a yellow question exclamation mark? ! or a red X Right click to reinstall drivers if you dont have a motherboard disk you will need to download the sound drivershttp://download.cnet.com/Realtek-AC-97-Driver-Windows-Vista-Windows-7/3000-2120_4-10962344.html
Realtek AC

Try pulling all but first slot memory stick, then reboot and see if that works. If so after set up add the rest. This worked for mine.

Hi,

Its seems to be your RAM is not working fine so remove your RAM from motherboard the clean the RAM slot and RAM the insert it again.

It will be work.

Regards

Ashly

http://www.asrock.com/manual/775i65GV.pdf

This will help you with that.

i would suspect the processor

The Motherboard limitation are DDR400 = 2GB maximum size per slot
Allthough you can with slower memory DDR333 or DDR266 go to the 3GB memory limit.
Due to the age it will be trail and error on the memory types. You won't necessary get any problems with the high density memory as long as it is good quality memory and you don't exceed the slot memory limit as mentioned above.
I recommend that you download the motherboard manual and read it.

Hi reynaldo_sos,

I'm not real sure that your problem is the motherboard. Have you checked to make sure that mute isn't on, and looked inside sound icon in your control panel to make sure that windows recongizes the sound card? If not, I'd check the easy stuff first. And if that doesn't work, you can find the drivers for that sound card HERE! Make sure that's the same version that you want.

Good Luck,

Mark

there are many drivers for your motherboard but tell me which operating system do you use--
any way try the following Link--

http://www.opendrivers.com/categorycompany/1364/11173/mainboard-drivers-and-utilities-ecs-free-driver-download.html