Problem(s). Not sure how related these are but ill start from boot up.
Bios says no OS, flashes, Bios again, then boots up. Bios is set to boot from the correct HD. but it boots up. not a big issue that i can tell, its just an FYI for the real issue that may or may not be related.
Real issue is the PC will not stay idle without issues. its very hit and miss. i leave the PC on 24/7 and it will have issues about once every 2 days.
the screen will be black, PC is powered (lights on PC, fans are running), no USB (i try plugging usb items in and no power). the PC will not wake up and i have to hold the pwr button to turn off.
I see nothing in the system logs and I've tried every power management setting including no power settings.
While the PC is locked the network is also locked. Any device connected to the home network has no internet connection including wifi.
If I'm using the PC, ill never have an issue, but leave it alone and it may or may not just lock up within ~2-72 hours.
Its always done this (a year now) and I've had enough and i cant figure it out myself.
adding more open ports (200)
changing power settings
updating mobo drivers /firmware
updating Video drivers
installing keyboard drivers for logitech G15 (unable to do this, PC locks up during instal)
Is the pc in sleep mode or standby, i know you said you adjusted power settings.
there is a setting in control>power settings>change plan settings>change adavced power settings
I would try to restore plan defaults
or under same section check usb suspend settings
Id say make sure you turn off hybernate I have had so many issues with that. Also if your PC if locking up during driver install you have more than a sleep issue. Is this system overclocked? Or does you motherboard auto overclock? I had a system that had auto overclocking built into the mobo and it caused no end of issues till turned off.. The issue was it was set to auto on default config and I had never even noticed it. Also test you ram is a good start. Look through you event logs for any clues might help too.
Another thing I noticed is your keyboard. I had an issue with my G510 that was causing lockups and video card driver failures shown in event viewer and it was related to windows sideshow. I resolved it by disabling windows sideshow options in the logitech console and then again disabling windows sideshow options at the bottom of device manager then the problem completely went away.