Introduction

HD 7990 Market Segment Analysis Radeon

HD 7950 GeForce

GTX 670 Radeon

HD 7970 HD 7970

GHz Ed. GeForce

GTX 680 Radeon

HD 6990 GeForce

GTX 590 PowerColor

HD 7990 GeForce

GTX 690 Shader Units 1792 1344 2048 2048 1536 2x 1536 2x 512 2x 2048 2x 1536 ROPs 32 32 32 32 32 2x 32 2x 48 2x 32 2x 32 Graphics Processor Tahiti GK104 Tahiti Tahiti GK104 2x Cayman 2x GF110 2x Tahiti 2x GK104 Transistors 4310M 3500M 4310M 4310M 3500M 2x 2640M 2x 3000M 2x 4310M 2x 3500M Memory Size 3072 MB 2048 MB 3072 MB 3072 MB 2048 MB 2x 2048 MB 2x 1536 MB 2x 3072 MB 2x 2048 MB Memory Bus Width 384 bit 256 bit 384 bit 384 bit 256 bit 2x 256 bit 2x 384 bit 2x 384 bit 2x 256 bit Core Clock 800 MHz 915 MHz+ 925 MHz 1050 MHz 1006 MHz+ 830 MHz 607 MHz 925 / 1000 MHz 915 MHz+ Memory Clock 1250 MHz 1502 MHz 1375 MHz 1500 MHz 1502 MHz 1250 MHz 855 MHz 1375 MHz 1502 MHz Price $340 $400 $440 $500 $500 $700 $750 $1000 $1000

AMD has been working on a dual-GPU HD 7990 card for a long time, but we are still waiting for a release. PowerColor has taken on the challenge and engineered a working HD 7990 by themselves, without any help from AMD.The PowerColor Devil 13 is the company's flagship limited edition hardcore enthusiast card. It uses two Tahiti XT GPUs running at HD 7970 GPU speeds of 925 MHz GPU and 1375 MHz memory. To enable an extra clock boost, a turbo button has been added which takes the GPU clock to 1000 MHz.Cooling for this immensely powerful card is provided by a custom triple slot, triple fan cooler which covers the whole card. Pricing of the PowerColor Devil 13 is $999, with limited volume available.All data in this review was obtained after I repaired a major design error of the card. When I received it, the card ran extremely high temperatures, reaching beyond 100°C, causing instability and black screen hangs. The fan would also run at 100% almost instantly. This is caused by screws with integrated stop that resulted in too little mounting pressure between GPU and heatsink, clearly an engineering oversight. I added three metal washers on each screw by removing the screws, adding the washers and putting the screws back. The cooler was removed for this procedure, and thermal paste was replaced with a thin layer. Only this procedure enabled the card to run stable. The card was unusable out of the box.