If you had a sudden drop-out you may have been zapped via the power demands. With all those devices, it may have taken its toll. Afterall, this is a simple electrical path with limited amperage going to it. I thought dust is the cause of the problem but a cleaning wouldn't hurt plus inspect the area for obvious damage(delamated solder run)or open. Also, possible ESD/static damage can be at fault. You can regain the ports if you add a USB card to replace those if applicable.
All Four USBs of the back of my computer are not working. I had to plug in devices in the front of my computer. It's a Compaq Presario I got in 2004. And I also have an equally loaded ViewSonic monitor with iPod dock. It has 4 USBs. I know I have 11 USBs combined.....But I still would like to know why 4 of them are out.... I tried restarting, and it didn't work...Could it be a tiny particles of dust thing?? Do I need a can of computer spray??