  We present the results of local, vertically stratified, radiation
magnetohydrodynamic shearing box simulations of magnetorotational instability
(MRI) turbulence for a (hydrogen poor) composition applicable to accretion
disks in AM CVn type systems. Many of these accreting white dwarf systems are
helium analogues of dwarf novae (DNe). We utilize frequency-integrated opacity
and equation of state tables appropriate for this regime to accurately portray
the relevant thermodynamics. We find bistability of thermal equilibria in the
effective temperature, surface mass density plane typically associated with
disk instabilities. Along this equilibrium curve (i.e. the S-curve) we find
that the stress to thermal pressure ratio $\alpha$ varied with peak values of
$\sim 0.15$ near the tip of the upper branch. Similar to DNe, we found
enhancement of $\alpha$ near the tip of the upper branch caused by convection;
this increase in $\alpha$ occurred despite our choice of zero net vertical
magnetic flux. Two notable differences we find between DN and AM CVn accretion
disk simulations are that AM CVn disks are capable of exhibiting persistent
convection in outburst, and ideal MHD is valid throughout quiescence for AM
CVns. In contrast, DNe simulations only show intermittent convection, and
non-ideal MHD effects are likely important in quiescence. By combining our
previous work with these new results, we also find that convective enhancement
of the MRI is anticorrelated with mean molecular weight.
