I have a sony vgc-rb30 I get 3 beeps when I power up. I have no video output, and the only peripheral that seems to work is the keyboard (at least the lights are on) I can't seem to find a motherboard diagram to tell me If cables are dissconected or something is in the wrong slot. I am using the on board video card, not an add on.

The problem is exactly with your RAM sir , the 3 beep sound is an intimation of RAM not detection from the BIOS , i will tell the procedure to fix the RAM , if you know to remove the side cover of the machine remove it by opening the back side screws, in the mother board you can see a vertically fixed chip is called RAM , the RAM is locked with the white color notch at the both ends of RAM , if you release that lock you can get the RAM separately, after it you, have to rub the contacts of the RAM to clean the fungus layer on the contacts, after that fix the RAM again by watching the small cut in the RAM , if you not getting the display than this have to replace the RAM only sir , this is the picture of the RAM , don't forget to vote for me