Hi I have an old 486 and earlier in the week I tried it to see if it worked I saw the processor digits on screen running and I went into CMOS but did nothing. Now on boot-up it shows FO on post-test card. I also get one long beep followed by two short, and one low buzz followed by one high buzz? I have changed the graphics card but no joy. There is nothing on the monitor at all now any ideas anyone.