Same thing here. Never seen anything like it before. I'm out of ideas. I suppose, as long as it finally does POST, just let it be.
I thought our motherboards might be the same, but nope, this is yours:
http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00496280&tmp_task=prodinfoCategory&cc=us&dlc=en&lc=en&product=1122478Mine is a Gigabyte, yours is an Asus.
Inspect all the motherboard capacitors to see if any have split open or are bulging.
Beware that not all capacitors will bulge, swell, and burst. They can fail and you would never know by looking at them.http://www.badcaps.net/pages.php?vid=5I d e n t i f y i n g - S y s t e m E r r o r s & S y m p t o m sHere are some functionality symptoms and issues your system might display if your capacitors are failing. Please note that these symptoms can occur even if your capacitors are not showing the physical signs demonstrated above. This is a rare occurrence, but it does happen. Most of the time, there will be physical signs of failure.
System Faults:
Motherboard fails to POST.
Memory Test Fails.
System randomly and/or constantly reboots itself.
Fails to fully boot (or even install) Operating System.
System randomly and frequently freezes.
Random & frequent 'Blue Screens of Death'
BSoD or hard freeze under heavy drive activity (Either RAID, SCSI, or standard ATA)
CPU temps abnormally higher than usual under typical or less load.
*CPU VCORE & other system voltages are erratic or far out of tolerances.
Resetting the system after a freeze and the system will not repost.
(You have to completely power down then power back up.)
*CPU VCORE & System voltage issues can also be associated with a faulty power supply. Before you decide your caps are bad, ALWAYS try a known good and high quality power supply.
If your capacitors display any of the above symptoms, there's a chance that you've got the plague. The more sporadic and random that the symptoms occur is usually a good sign of bad caps. However, you should double check any and all drivers and other hardware FIRST! Some of these symptoms can easliy be mistaken for other computer problems! Although, if you've already done that and your system is still acting like this, there's a good chance that you may be faced with breaking out the 'ol soldering iron!!