Now, I have a video on this on YouTube, but I still have yet to find the solution. I have a Compaq Presario 7AP140 (10 years old, so what?) that has no POST and has fan maxed out (well, always is) with an orange/yellow power light. HDD light stays on for a minute or two, but no POST. It somehow started one day last summer when I started it up from standby. Everything seemed normal, but after 15 seconds, the screen went blank, green light switched to orange. So, I powered it off, hoping it was a temporary problem. However, it was not. At that point, it had no boot for 2 days. I had dissected it, switched power supplies (3, original 150 W, generic 30 A 12V 300 W, and generic 42 A 12V 400W), but, sadly no boot. 9 months later, I am left to think that it was a loose processor (Slot A, Athlon 800 Mhz). If any solutions come up, I will try and get it running again. If not... farewell, humble Compaq Presario.

It's time for last rites and a trip to pc heaven.