I know it's not a block, but I used a NZXT Kragen G12 and Corsair H55. The G12 fit using the AMD adapter. The only problem I had was adapter clearance with two 20mm copper heatsinks on the VRAM. I used tape on those instead. I went with the H55 for simplicity. I didn't want to deal with another RGB and I'm out of USB spots on the motherboard.