Thanks to you all for your responses to this issue. @OldPhil: I appreciate your detailed suggestion and keep in it mind.
@patriot / @bludshot
I can't be sure if it's all or just one/two of the USB ports that are problematic. I was only using the front ones for my portable devices. I have my mouse and keyboard plugged into 2 of the four rear USB slots, and I have had no problems with those, as far as I know.
The devices were sitting on top of the desktop, while they were plugged into the front USB slots. I have been keeping things here for years without any problem, so I doubt this is an issue. The front USB ports were apparently plugged into a header on the motherboard, because I unplugged two cables from the 2 (of 4) F_USB headers that were being used and the front USB switches (and the flash card reader, of which they are a part) stopped working. The back ones, however, are still working. There aren't wires/cables running from the tiny silver boxes where the back USB switches are located, so I am assuming that they are a physical part of the motherboard.
Some photos I took when the case was open:
The first pic shows the silver boxes housing the USB ports in the back of the machine. The second pic shows where the front USB stuff was apparently hooked up. The unplugged wire is a 1394 cord that I wasn't using, so I unplugged. After I took these pics, I also unplugged the black and the white wires, which were plugged into the "USB 1" and "USB 2" headers. Doing this effectively killed the functionality of the front panel. (Pardon me if I'm overexplaining--I don't usually open up computer cases and don't know much).
So this is where I stand now. In your opinions, is this a safer way to move forward, by using the remaining back USB ports, perhaps with a powered USB hub? In other words, is a power problem I've experienced in the front likely to also occur in the back?
THANKS...hope to put this issue to rest soon.
Edited by Schubie, 02 March 2014 - 12:59 PM.