I used my 64gb San Disk thumbdrive to load an ISO of Windows 10 for installation. That was fine, but the ISO tool that you download from Microsoft reformats your USB drive. I now want to use it again and reformatted it with whatever default came up (happened to be NFTS). I read that exFAT is actually what you want to use for thumb drives. I reformatted again to a 128k allocation size, exFAT. I copied a 2.5gb file onto the drive to test the speed and it is going at about 80mb/sec. This is from a 3.0 port (I guess technically it would called 3.1 generation 1) type-A connection on the mobo rear panel. I did not test the 3.1 generation 2 port, but the speed shouldn't change since the actual drive is only 3.1 gen 1. 80mb/sec is about as fast as I can recall this drive ever performing. However, when I put the drive into my laptop to do a backup (which is what I primarily used it for anyways), and it will only transfer at about 25kb/sec. What is going on? Should I reformat it and change the parameters? Should I do the non "quick-format"? I would doubt anything is wrong with the laptop as it worked just fine a few days ago.