The MS6905 Rev. 1.1 does not have the voltage jumpers of the Asus S370, but it also enables dual-mode for Celerons by default.
Many people still think that using two CPUs in a dual motherboard doubles the performance.
But don't be disappointed if you won't notice any obvious performance gain. Two performance-hungry tasks are usually enough to slow down your system considerably. So it's no problem to work on a Corel Draw project while rendering an overkill scene in 3D Studio Max. You can even write a CD while processing large images with Photoshop. The second way of benefiting from a dual processor system is using multi-threaded applications, which have been optimized for multiprocessor environments.