I have Compaq SR5450F desktop. Earlier this week I woke it from sleep mode, but rather than waking it just started beeping; one long beep (about 15 seconds) followed by a long pause (about 10 seconds), repeating indefinitely. Compaq/HP support indicates a serious problem with the CPU or motherboard. I have tried troubleshooting to eliminate memory and peripherals, but the problem seems to point to the cpu or motherboard. Is there some way I can tell if one or the other (or both) is the culprit? The computer does not boot at all.