Matrox, along with S3, develop GPU ASICs for use with desktop add-in boards, alongside AMD and NVIDIA. Last year, they sold less than 7000 units in their quarter according to my math (rounding to 0.0% market share implies < 0.05% of total market, which was 7000 units that quarter). Today, Matrox Graphics Inc. announce that they will use an AMD GPU on their upcoming product line.
While they do not mention a specific processor, they note that "the selected AMD GPU" will be manufactured at a 28nm process with 1.5 billion transistors. It will support DirectX 11.2, OpenGL 4.4, and OpenCL 1.2. It will have a 128-bit memory bus.
Basically, it kind-of has to be Cape Verde XT (or XT GL) unless it is a new, unannounced GPU.
If it is Cape Verde XT, it would have about 1.0 to 1.2 TFLOPs of single precision performance (depending on the chosen clock rate). Whatever clock rate is chosen, the chip contains 640 shader processors. It was first released in February 2012 with the Radeon HD 7770 GHz Edition. Again, this is assuming that AMD will not release a GPU refresh for that category.
Matrox will provide their PowerDesk software to configure multiple monitors. It will work alongside AMD's professional graphics drivers. It is a sad that to see a GPU ASIC manufacturer throw in the towel, at least temporarily, but hopefully they can use AMD's technology to remain in the business with competitive products. Who knows: maybe they will make a return when future graphics APIs reduce the burden of driver and product development?