During start-up, the system may not detect the Serial-ATA hard drive, instead the machine continues with the next device selected in the startup sequence. Failure is intermittent and occurs approximately once in every 200 boots.

Any of the following systems configured with one of the following Serial-ATA hard drives: FRU 71P7312 - 40GB 7200RPM 7 PIN Serial-ATA; FRU 71P7293 - 80GB 7200RPM 7 PIN Serial-ATA; FRU 71P7297 - 160GB 7200RPM 7 PIN Serial-ATA

• ThinkCentre A30 (type 8198)
• ThinkCentre A50 (type 8320, 8419)
• ThinkCentre A50p (type 8192, 8193, 8194, 8195, 8196, 8197, 8432, 8433)
• ThinkCentre M50 (type 8128, 8185, 8186, 8187, 8188, 8189, 8190, 8413, 8414, 8415)
• ThinkCentre S50 (type 8183, 8184, 8416, 8417, 8418)

Do not replace any hardware for this issue. Update the system Bios to the most current version. As of this writing, the latest system Bios file name is 2ajt46a.exe and can be downloaded from the following URL:

http://www.lenovo.com/think/support/site.wss/MIGR-51058.html

Please refer to the accompanying text files for driver installation instructions. Restart the system.