Recently built a 5820k based system with a Gigabyte X99 UD3P board, installed all latest drivers again, enabled xHCI mode everywhere in the bios (and disable EHCI to be sure) but my USB 3.0 devices still connect at USB 2.0 speeds. At the first, I though it was a front port issue (have seen that happen before), but the same thing happens with the back ports too. In particular I'm trying to get a sanddisk cruzer fit 3.0 to connect at 3.0 speeds to no avail. Also tried an external hard disk that connects to my laptop (Intel Haswell based as well) at usb 3.0 and even that connected at usb 2.0 speeds. The device manager shows the 'generic super speed hubs' correctly. Not sure what gives here. Also made sure that no USB 2.0 device is connected to the same hub, still no dice. Tried every combination of xHCI Hand-Off (currently off), eHCI Hand off (currently off), USB Legacy Support (currently off) and xHCI Mode (from Smart Auto to Manual, currently set to enabled) but no dice. Really frustrating, thought pcs were becoming easier to build, not harder. Almost wish I had kept my SB system. Can our wise editors who recently reviewed the very similar x99 UD4P board with the same F2a bios comment on what settings they used?