In my case I had to install the old 'mg_snd_sse.dll' and 'mg_snd.dll' from 4.08 to get 4.09b1m to run on my Athlon XP 2000+ cpu.
Seems many others have same issues
SimHQ thread about it here:
http://www.simhq.com/forum/ubbthread...48#Post2409248
the two core dll's seem fine from 4.09b1m on my lowly FX5700LE vid card and I have no graphics issues