If you are using the Maxximus007_AUTO_TEMPERATURE_CONTROL  ensure you are also changing the individual powerlimits for each GPU:

for a 1080ti I recommend using between a 200 and 225 powerlimit.

If you have already done this:

It is also possible there are some bad sectors on your USB key and they are causing problems.  I have had 5x USB keys go bad so far; although I do reimage a lot with test rigs.

It might be a good idea to try using another USB key or SSD.