Elite Bastards posted a review on the Sapphire Radeon HD 5870 1GB video card

A reference Radeon HD 5870 makes use of a full Cypress core with all of its Stream Processors, texture units, ROPs and so on intact - Couple that with an 850MHz core clock speed and you have yourself 2.72 TeraFLOPS of computing power to play with. Meanwhile, this board also features 1GB of GDDR5 memory sporting a total of 4.8 Gigabits per second of bandwidth courtesy of a 1200MHz clock speed.

Sapphire Radeon HD 5870 1GB video card review