Control panel.. power options set it to high perf.
Now go through each option in the plan and set it to never or off or whatever it's called.
Control panel....device manager.
Go through each usb device,hub,controller/properties/power management.
No turn off allowed.
I've been having a really weird problem with my PC where after 45 minutes to an hour my USB devices all shut off and I can't reconnect them without restarting. It's been a pretty persistent and annoying problem and I can't seem to figure out what the cause is. I've replaced several pieces of hardware already including the motherboard but I still cannot seem to stop these failures. Here are my specs:
Windows 7 home premium 64x bit O/S
CPU Intel Core i7 2600 @ 3.40GHz
Graphics 2048MB ATI AMD Radeon R9 200 Series
RAM 8.00GB Dual-Channel DDR3
Storage 1863GB Hitachi HUA723020ALA641 ATA Device
Intel BLKDH77EB LGA 1155 Intel H77 HDMI SATA 6Gb/s USB 3.0 Micro ATX Intel Motherboard

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