name check
I asked many including lawyers about name check and FP. It seems that name check is requested by USCIS to FBI when they receive your 485 application. Once your FP is completed, FBI will send back FP results along with name check results to USCIS. If you name does not match any record in FBI, it just takes very short times, say less than 1 hour to complete your name check. But if you hit some record unfortunately, you have to wait for further screening, which could be manual operation. This strongly depends on your luck although most of chinese applicants are fine with FP and name check.