10-25-2017 10:17 AM
Found pc screen had not entered sleep mode one morning. Shut PC down. Later turned it on and got blue screen with HP Logo and msg to “enter esc...” tried a number of things but could not get Pc to boot. I got to the point where I was going to try opening the back of the PC, removing and checking hard drive (with a USB to SATA/IDE Hard Drive Adapter and a laptop), I disconnected it, walked PC 20 feet to table with blanket, sat it down face first. But then remembered I forgot to check if I had removed the CD. So I returned PC to office, plugged in power cord, turned on PC to see if CD was in it but THIS TIME THE COMPUTER STARTED SUCESSFULLY!
Seems to be OK now. One final note, about a year after I bought it I returned it to HP under warranty for I think a similar reason. They returned it with a note that NO DEFECT WAS FOUND. PC appeared to be OK.
A year later it happened again and went back to HP a second time. This time they replaced the motherboard and memory, under warranty. I wonder if all three occasions were the same problem.
Any educated guesses?
10-25-2017 02:04 PM
Two years ago, you completely unplugged the PC's electrical power, moved it, and replugged the PC.
That total loss of power could have been all the "remedy" that was required.
You moved the PC from location 'A' to location 'B', and twisted it from "face-out" to "face-down" position.
That movement could have "flexed" some intermittent connection, or could have dislodged some dust.
Last year, you shipped the PC to HP, and they shipped it back to you, saying 'NO DEFECT'.
Again, there was physical "jostling" of the hardware.
Then, for a second time, you shipped the PC to HP.
Maybe, they found something, making it NECESSARY to replace some components.
Maybe, by the technique of "part-swapping", they produced a working computer, and thus stopped their trouble-shooting, because it was now working, which was their desired result.
Maybe, they kept the original RAM, and original motherboard, and did further diagnostics, after shipping the repaired system back to you.
Probably, the RAM ended-up in the technician's inventory of spare parts.
Given that HP has a warehouse stocked with brand-new motherboards identical to yours, it is not economic for them to do any further trouble-shooting of the original, well-used, motherboard -- they probably just threw it into their end-of-life "recycle bin". They would never put a "used-but-suspicious" motherboard into some other customer's HP computer, to try to repair that other person's computer.
10-28-2017 08:55 AM
Mdklassen’s response is very much aligned with my thinking. I’m no expert but I’ve opened computers to install memory, swap hard drives and install cards, etc. and computers seem to be fairly sturdy. This one sets on a desk in a home office and in never moved or jostled and very little dust. I Suspect all 3 occasions have the same root cause but it’s strange that in occured again after swapping out motherboard and memory. I also think others may have had similar experiences.
10-28-2017 12:56 PM
One thing that I did not mention was AC power, as supplied by your electrical utility.
If that is not "smooth", or is "spikey" (think 3rd world & brown-outs), and you don't have either a surge-protecting power-bar or a UPS (uninterruptible power supply) feeding your computer, then you might have an ongoing "power" issue.
10-30-2017 07:45 PM
RE: Boot issue. HP desktop BIOS contaiins a harfdcoded emergency bios last boot reset option which is activated when power is removed from the deskjtop and the power sw is held down for a number of seconds. (book states 15) . This clears the last boot data stored from the last shutdown. IF your last shut down resulted in a conditioon that caues your box to hang when you restart it will go right back to the hang sequence. (W10 is famious for this.) When u unplugged the box you triggered the clear sequence.