For the last few weeks I have had a problem with the Cabin Altitude Warning coming on.  I have been careful not to over-rotate on takeoff so I don't think it is a tailstrike event causing the problem,   I saw a post that this warning can be caused by a bios clock issue.   I noticed that my PC was not keeping correct time a few weeks back and I've got an ASUS Sabertooth Z87  motherboard which have been reported to be problematic.  I've setup Internet Time Sync so my PC time now shows up correct but I saw the post that a BIOS update may be needed to allow the PMDG 777 to work properly.  I don't really want to start flashing BIOS if I don't have to.  Suggestions welcome.

 

 

I noticed that my PC was not keeping correct time a few weeks back and I've got an ASUS Sabertooth Z87  motherboard which have been reported to be problematic.

 

This is the issue. ASUS boards have been plagued by this for years.

 

Check your CMOS battery first, and replace as necessary. From there, flash the BIOS. Either or both of those should stop the issue.