Hey guys,
  So my mame machine crashed a while back.  But when it worked, I had it running groovymame(I think) and calamity's drivers(for sure).  It worked great!  What I really liked was I could switch resolutions in game via the, ''' and ',' buttons.  
After rebuilding the machine, it seems that the ''' and the ',' don't do anything.  I tried it on both Calamity's 6.5 and  9.2 drivers...I'm wondering if I'm missing a config somewhere...it's been so long I can't remember...in fact, I can't be 100% sure if that feature was a groovymame thing or a calamity thing...
Anyone know?