  We present a precise estimate of the bulk virial scaling relation of halos
formed via hierarchical clustering in an ensemble of simulated cold dark matter
cosmologies. The result is insensitive to cosmological parameters, the presence
of a trace, dissipationless gas component, and numerical resolution down to a
limit of ~1000 particles. The dark matter velocity dispersion scales with total
mass as log(sigma_{DM}(M,z)) = log(1082.9 +- 4.0 \kms) + (0.3361 +- 0.0026)
log(h(z)M_{200}/10^{15} Msun), with h(z) the dimensionless Hubble parameter. At
fixed mass, the velocity dispersion likelihood is nearly log-normal, with
scatter sigma_{ln sigma} = 0.0426 +- 0.015, except for a tail to higher
dispersions containing 10% of the population that are merger transients. We
combine this relation with the halo mass function in LCDM models, and show that
a low normalization condition, S_8 = sigma_8(Omega_m/0.3)^{0.35} \= 0.69,
favored by recent WMAP and SDSS analysis requires that galaxy and gas specific
energies in rich clusters be 50% larger than that of the underlying dark
matter. Such large energetic biases are in conflict with the current generation
of direct simulations of cluster formation. A higher normalization, S_8 = 0.80,
alleviates this tension and implies that the hot gas fraction within r_{500} is
(0.71 +- 0.09) h_{70}^{-3/2} Omega_b/\Omega_m, a value consistent with recent
Sunyaev-Zel'dovich observations.
