Problem with 4GB DDR2 Memory

gabernardone wrote: I have an ASRock G31M-S (Bios Version P2.10), currently it is with a Core 2 Quad 9550 and a GTX 750TI. 1x 2GB DDR2 and 1x 4GB DDR2 (Total 6GB). I had a problem with this motherboard that stopped video, the card was turned on, the coolers were running, but no video came out). I bought another one and the memory card of Markvision 4GB DDR2 800Mhz is no longer being recognized, I'm sure it is not broken because I tested it on another motherboard and it worked, but when I put it on the ASRock G31M-S, it is without video and there is no beep in BIOS. Can it be some BIOS setup? The memorys cards have the same bus. Honestly I'm scared to have lost this 4GB DDR2 memory so hard to find.

Sorry but I am confused by your description of the situation.

First you lost the video signal from the video card. Then you bought "another one" which means a video card, is that right?

Then you said the 4GB memory is no longer recognized. But how do you know the memory is not recognized if you have no video signal from the PC with a video card?

Did you use the on board, built in video? Did that let you see in the BIOS or Windows that the memory was no longer recognized?

If you tested the 4GB memory in another PC, and it works, then something else is wrong and the memory is fine.

If you don't get the single POST Ok beep, something is not working correctly. But you don't hear any other POST beeps at all? If the video signal just stopped one day, and you did not change anything in the BIOS, how can that be a BIOS setting problem?

I don't understand why you think the memory is causing no video signal. Does the PC start with only the 2GB memory in the board?

Does the PC start with the built in video? Did you try removing other devices like your HDDs or optical drive to test if they are the problem?

Do you know how to clear the CMOS/BIOS with the jumper on the board? That is shown on page 18 of your board's manual. Clearing the CMOS/BIOS can sometimes fix problems, but I cannot guarantee it will fix your problem. If you have changed any BIOS settings from their defaults, clearing the CMOS/BIOS will set everything to the default value, so you will need to set them again. Your board's manual:

http://asrock.pc.cdn.bitgravity.com/Manual/G31M-S.pdf

Another thing to consider is that board and CPU are old now, they both could be up to nine years old. A part on the board might have failed. How old is the PSU you are using? Did you try using another PSU as a test? If you have tried two video cards and they work in another PC, and the 4GB memory works in another PC, then those two things are not the problem. You need to start checking other things, like the board itself. As I said, can you get a video signal from the board's built in video?