Today we are taking a look at our first ever retail ATI Radeon HD 5870 graphics card, which would be the ASUS EAH5870 Voltage Tweak! Rather than just selling a reference designed card, ASUS has developed something called "voltage tweak technology" that only works on graphics cards with their custom vBIOS. Does this really matter to you? Well, according to ASUS the ability to adjust the voltages could mean up to a 38% boost in performance. This is not bad at all; the ability to boost GPU voltages via the ASUS SmartDoctor utility is a great thing for gamers and power users.