Congratulations getting your hardware issues sorted out. If I remember right, this system came to you without a hard drive and you said you had one to install.
Of course you did a fresh install of the operating system... right? You are not trying to run this system on an old installation from another system I hope!
If you performed a fresh install skip the next line and please proceed with the rest of this post.
If you didn't do a fresh Installation, please consider doing so before anything else. You are doing more harm than good if you are trying to use an installation from another system on this one!
You mentioned needing drivers for USB which should be available from the motherboard manufacturer or if you have an add-in card, they will be available from the card manufacturer.
If you would be so kind as to download and install Speccy: http://www.bleepingcomputer.com/download/speccy/
Run the program. When Speccy finishes Click File > Publish Snapshot > Yes.
Please copy/paste the link in the Publish Snapshot window to your next post.
Please download MiniToolbox: http://www.bleepingcomputer.com/download/minitoolbox/
Launch the program, check all entries and click GO, Please copy/paste the results of the scan in your next post
Lots of luck and Please keep BC posted