The Challenge L is multiprocessor capable. If it's an L then it one of the deskside cases and can fit 3 CPU boards. Depending on what CPU family you use, you can have up to a maximum of 6 or 12. The Challenge series don't come with a graphics subsystem but I think you can use an Extreme graphics subsystem if you get the right adapter.

It's not going to be light but it's not as a bad as the rackmount case. The rackmount case fully populated was around 350kg.