Asus P8Z77-V LX USB power problem?

[Pajda]

Hello community,

I am having probably a USB power problem that I have absolutely no idea how to fix.
I have a Steelseries Merc Stealth keyboard, Razer DeathAdder mouse, TPLink USB wifi Dongle and occasionally a HP printer connected to my USB ports.
It happens multiple times that when the computer boots, the keyboard (illuminated) does not respond, does not light, is not detected at all under Windows. Replugging the keyboard has to be performed several dozens of times to be able to be detected properly. The same happens when I bring the computer from sleep, + from this mode the wifi dongle is not powered on, either. Device manager shows an unknown device if undetected. When booting, BIOS seem to detect the keyboard without issues, as it responds to Del key and it is illuminated.
I have latest BIOS flashed, AI suite from ASUS.
ASUS support thinks it is the driver problem or a firmware in the keyboard.
SteelSeries support thinks its the motherboard problem.

Specs:
Windows 7 64bit
ASUS P8Z77-V LX
Intel Core i5-3570K
Kinsgton DIMM DDR3 1333MHz 2x4GB
nVidia GeForce GTX 550 Ti

 

[Mohammed Adhil]

http://steelseries.com/downloads Download The Latest Driver Of Steelseries Merc Stealth keyboard
For Razer Visit http://drivers.razersupport.com/index.php?_m=downloads&_a=view&_m=downloads&_a=view
TP Link http://www.tp-link.com/en/download-center.html

If They Don't Work Try Download Universal Hub Controller (USB) Controller https://www.asus.com/Motherboards/P8Z77V_LX/HelpDesk_Download/

Try Downloading From Under USB Section

 

[Nuwan Fernando]

What's your PSU?

 

[Pajda]

http://steelseries.com/downloads Download The Latest Driver Of Steelseries Merc Stealth keyboard
For Razer Visit http://drivers.razersupport.com/index.php?_m=downloads&_a=view&_m=downloads&_a=view
TP Link http://www.tp-link.com/en/download-center.html

If They Don't Work Try Download Universal Hub Controller (USB) Controller https://www.asus.com/Motherboards/P8Z77V_LX/HelpDesk_Download/

Try Downloading From Under USB Section

I have all these drivers installed. I checked if it is the latest version, for TPlink I updated it.

What's your PSU?

I have a Chieftec 500W PSU.

 

[Nuwan Fernando]

Sorry! I was having a vacation.

Since you have a 550ti, Your power supply must be giving it's full power to deal with the requirement. Try changing the PSU.