POINT NO.1- If you install more than 4 GB of ram on a motherboard, (I.e: let's say for the hell of it, you install 12 GB for example), and you then install any 32 Bit version of any windows operating systems, the motherboard for reasons I'm don't fully understand myself anyway, will only report and use the first 3 GB of that 12 GB ram, the remaining 9 GB will be ignored and not used.
POINT NO.2 - If you install more than 4 GB of ram on a motherboard, (I.e: let's say for the hell of it, you installed the same 12 GB again just for an example), and you then install any 64 Bit version of any windows operating systems, the motherboard for reasons I'm don't fully understand myself anyway, will only report and use the first 3 GB of that 12 GB ram, the remaining 9 GB will be ignored.
Thinking more in-depth about this, I think the reason why all motherboards only see a small majority of ram when large amounts of memory are installed, has something to do with 2 things...
1st, the PC's binary code is programmed using only zero's and '1's which is the bios's programming language which is every computers main default running language, this CANNOT be replaced, changed, altered or manipulated or tampered with in any way.
2nd, when Microsoft start writing in a beta format, a brand new language that they incorporate into that new system, it's written in such a complicated way that even before you install it, it automatically detects and searches for what hardware you have connected to your motherboard, what version that hardware is, then it communicates directly with your BIOS program, then it checks your hard disk partitions and how big your hard drive is, then it checks to see if the motherboard is able to cope and support it's language, and then, if all those check results come back as true, THEN it will go ahead with the installation.
Nowadays of course we don't have to use sata drivers to configure and format our hard drives, the operating systems do all the work for us which is extremely useful....but as for why your USB isn't working on a 64 bit system, the answer is simple....your drivers for the USB are not the up-to-date and right ones for your OS and motherboard.
Check the specs,
Chris