This sounds odd, I did a quick test of Outrun 2006 on my GTX 980 on Win8.1 and it worked fine, not reinstalled it yet after installing hundreds of other games though.
Maybe a Windows update knobbled something? I do get issues with numerous games on mine, crashing randomly to desktop, but they tend to be late 90s-mid 2000s games like NFS Porsche and NFS Hot Pursuit 2, haven't yet debugged them, as some people with similar set up say they run fine.
Could be issue with Nvidia newer drivers, or some other drivers, or RAM?