Sapphire HD 7990 “Atomic” PCB and Cooling Solution Detailed
Ryan Martin / 4 years ago
Sapphire’s HD 7990 Atomic graphics card was revealed at Computex 2013 earlier this year and we took a look at the early version of it. The PCB has now been pictured and as you can see it features a huge density of electrical components. The heart of this new graphics card from Sapphire is a pair of highly clocked 28nm Tahiti XT2 GPUs (aka 7970 GHz Editions) with 3GB of useable VRAM (thats 6GB total, with 3GB in parity). The PCB uses a PLX PEX8748 PCIe 3.0 x48 bridge chip for maximum bandwidth while there is an 18 phase VRM that draws power from three 8 pins to power this monster.
Each GPU has 6+2+1 pyhase VRM (VCC+VDDCI+MVD). The VCC uses two 50 amp chokes per phase and driver MOSFETs. The ancillary phases use LFPAK MOSFETs while Tantalum capacitors handle most of the electrics on the 12 layer PCB. The PCB has two sets of video BIOS for each GPU and the display outputs are six mini DisplayPorts. This card can CrossFireX with any other HD 7990 using the connector.
The cooling solution hasn’t changed much since Computex though Sapphire have swapped out the “toxic green” tubing for a plain black. Other than that it looks like a pretty standard 45mm thick 240mm radiator with a pair of 120mm fans and a reservoir/pump hybrid bay device which appears to be 5.25 inch in form factor. The included fans do 1200 RPM.