Hello, I'm new here so there's my problem: I have Lenovo Thinkcentre M57 6395-AB5 USFF PC. Decided upgrade CPU from E2160 (M0 Core Stepping) to E8400 (E0 core stepping), as it is stated that E8400 is supported by 6395 system: w w w-307.ibm.com/pc/support/site.wss/document.do?sitestyle=lenovo&lndocid=MIGR-69254 My BIOS update version 54KT23A is the latest, downloaded from there: w w w-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-69695 As I see from BIOS flash files there's CPU microcode for E8400 C0 stepping only. When I installed my E8400 E0 stepping, got two beeps and POST error "167 no processor BIOS update found" and FAN goes at full speed (about 5500 rpm all the time). It continues to load to windows. In windows environment all seems ok, despite constant full speed fan. So it seems E8400 E0 stepping is physically supported by my system. I have googled for the info, and found out that my BIOS version needs to be updated with E8400 E0 core stepping CPU 1067A microcode. Maybe somebody can help me with adding E8400 E0 core stepping CPU 1067A microcode to my BIOS flash files? Thanks.