CrossFire X : recap of gains
After having compiled all the previous results, here are the average gains we obtained with CrossFire X in the various test configurations:
As we suspected combining a Radeon HD 3850, or more particularly its 256 MB, with a faster Radeon seriously limits performances. This is therefore a solution to avoid.
Also, we still noted differences in performances between a couple of Radeon HD 3870s and a Radeon HD 3870 X2. We believe that it comes from the fact that the X2’s GPUs only communicate via the PCI Express bus as there doesn’t seem to be a CrossFire connection on the PCB. Moreover, this is something AMD confirmed in the beginning; however, this manufacturer seems to have recently changed its mind telling us that there is indeed a CrossFire type connection that is present and functional. So what should we believe? While waiting for clarification from AMD, it seems that given our results the first answer is the most probable.
