Hello Gradius! Thank you for sharing your knowledge. I also came to BSY problem with my sister's Seagate 7200.11, however, disk still doesn't to boot after procedure I've gone through. - I've made first BSY step change. - Bios now recognizes HDD - Tried to boot from disk, no go. - I've made first second BSY step change. Here is serial console log from second (optional) BSY step: F3 T>i4,1,22 F3 T> F3 T>m0,2,2,,,,,22 Max Wr Retries = 00, Max Rd Retries = 00, Max ECC T-Level = 14, Max Certify Rewr ite Retries = 00C8 User Partition Format Successful - Elapsed Time 0 mins 00 secs - Partition format was very quick, instant. - Disk still doesn't boot. - Now I've used diagnostic SeaTools from Seagate. - Done Short test and I've received answer ADEACE62, that I dish has bad blocks - Done Long test and I've received answer that there are 100 errors (error was at all but very first block ). I didn't have any problems with RS232 part or moving powered PCB back to HDD body. My question is, if you can confirm me, if I've done something wrong. I'm not sure if it was correct to do (second) optional BSY step, because first one already solved BSY problem (but disk didn't boot). Thank you in advance, Borut.