Hey guys.
Long story short, last night around 1am (AEST) my COMPUTER was working fine, I left it on and went to bed, nobody has access to my room, and since I was asleep, the computer would have been kept the way it was. This morning, I woke up, to which no surprise, my pc was still on, just the MONITOR was on standby, again, nothing unusual. I tried moving my mouse as I usually do to get my pc to wake up and become active again, but it didn't, confused, I tried typing, turning the monitor on and off but to no success.

I turned my pc off and tried again, but same issue occured. Take in mind I have an led lit mouse and keyboard and usually when I turn my pc on, they lit up instantly, but they didn't, and neither did my monitor, it ran the standard asus LOAD up screen then said DVI can not be found. So this means that both the motherboard ports that I usually run my mouse, keyboard and webcam through aren't responding to those devices, because I run a card reader through the front usb ports, I tested that on the back, and it worked, and the graphics card dvi slot isn't responding, I tried running my dvi through my motherboard port, but it's still saying that the DVI can not be found.

After opening up my case, nothing seems to be out of place so I don't understand what could be wrong.

Incase you're wondering, my specs are :

ASUS P8Z77-V LX Motherboard
Intel i5-3570k CPU
HIS HD7850 2G GPU
8GB of old DDR3 ram ( not sure of the maker )
WD 3.5" Blue 1TB Sata3 HDD.

Due to being unable to access the bios since my monitor and keyboard don't work, does anyone know any ways of fixing the issue ? Thanks.What is wattage of power supply? Have you tried running computer with integrated video only and video card removed to see if anything changes with symptoms?

* I have had bad luck with HIS brand cards btw. High failure rate in the bunch I bought for graphics department of a company that I supported.

I run a dual-video ASUS ATI AMD 5450HD VGA/DVI combo and only issues I have are if I am running dual-displays and use my KVM to SWITCH my VGA display, my card gets confused with it going from dual-video out to single video out DVI that is CONNECTED directly to the card. When doing this my audio will make the da-dunk sound same as when a USB thumb drive is removed and I lose my VGA out to a black screen until I reboot the computer. But your issue is far worse if you are losing USB ports etc which may be power supply issue when related to video card also not wanting to behave.I've tested numerous things, I decided to get an adapter and run my monitor with VGA through to my laptop, same as my mouse and keyboard, and they're working fine. I think I may have an issue with my motherboard, I've had it for around, 6 months and use it everyday for hours on end.
I think due to the high stress it's been under, it's lost capability and is no longer receiving connectivity from the ports.

The power supply I run is a bronze 600W.
I'll be working towards a new motherboard over the course of the next 2 weeks, if the new motherboard fixes the issue, I'll leave an updated post here for anyone else who may have an issue like this in the future.