Dimension 5100 light show

My Dell Dimension 5100 took a dump this morning. It would cycle between the CDROM, Hard Drive, Diagnostic codes 34, 24 and 1. It would not even try to start just keep flashing the cycle of lights on the front display. If I disconnect absolutely everything it will just come up with code 1. If I leave one memory module if or the graphics card it will show code 123. With both memory modules in (256 MB each) or just one and the graphics card it goes back to the cycling light show. None of the other devices, Drives or cards make any difference.

Any Ideas anyone? I keep coming back to some problem related to memory or data buss, as the only things that seem to make any difference are cards with RAM.

Bottom line it looks like my motherboard, CPU or both are toast.

Now the diagnostic lights are not working but it is still in the same loop (from the CD light).