AMD Radeon HD 6790 1GB Video Card Review

The AMD Radeon HD 6790 Graphics Card

Tonight AMD is releasing another new video card called the Radeon HD 6790. This video card shouldn't come as too much of a surprise as they were made available on the retail market before the card officially announced by AMD. The AMD Radeon HD 6790 isn't a revolutionary change, but it is more of an evolutionary change. What do we mean by that? Well, the AMD Radeon HD 6790 is nothing more than a 40nm Barts core that has some things disabled and the clock speeds adjusted. Remember when AMD announced the AMD Radeon HD 5870 and Radeon HD 5850 graphics cards back in 2009 and then followed both of those up with a Radeon HD 5830? That card used same PCB that the Radeon HD 5870 used, but had more stream processors (ALU's) disabled that either the Radeon HD 5850 and Radeon HD 5870. It made up for the disabled stream processors by having a higher clock speed than the Radeon HD 5850, which meant it also consumed more power. It was a very strange card, but it worked and fit in the Radeon HD 5800 series as it used a "Cypress" core. Think of the AMD Radeon HD 6790 as a Radeon HD 6830.

AS you can see the AMD Radeon HD 6790 fills in the gap between the Radeon HD 6850 ($144.99) and the Radeon HD 5770 ($99.99). The AMD Radeon HD 6790 has an MSRP of $149.99 and is already available in the market. We expect the AMD Radeon HD 6790 to fall in price in the days to come as numerous AMD Radeon HD 6850 video cards can be had for $145-$150 after rebate. We figured the AMD Radeon HD 6790 would be called the Radeon HD 6830 and it looks like many others thought this way as well as AMD issued this statement on the nomenclature of the card:

"The AMD Radeon HD 6790 products are positioned between our AMD Radeon HD 6850 and the HD 6770 (the OEM equivalent of the HD5770). The performance of the HD 6790 is roughly 20% higher than the HD 5770/6770, which makes a lot of sense when you consider the performance difference between most HDxx50 and HDxx70 products. Juxtaposing the product's specifications may shed some additional light on this. The AMD Radeon HD 6790 shares many 3D engine configuration similarities with to the rest of the AMD Radeon HD 6700 Series. Namely, the 800 stream processors are common across the HD 6790 and HD 6770, while 16 render back-end units are common across the entire HD 6700 Series of products. Ultimately, we are trying to help buyers better understand just the performance of the product by providing what we feel is the most descriptive branding." - AMD Marketing

That being said we still feel that AMD should call this card the AMD Radeon HD 6830 to keep it consistent with what they did on the last product series.

As you can see the AMD Radeon HD 6790 has a 840MHz core clock and a 1050Mhz memory clock. The card has 800 stream processors and is rated as having 1.34 TFLOPS of compute power. Not bad numbers and you can see how it stacks up to the AMD Radeon HD 6850 and Radeon HD 6870 below.

	Core Clock	Memory Clock	ALU's	Board TDP	TFLOPS
AMD Radeon HD 6790	840MHz	1050MHz	800	150W	1.34
AMD Radeon HD 6850	775MHz	1000MHz	960	127W	1.5
AMD Radeon HD 6870	900MHz	1050MHz	1120	151W	2.0

The AMD Radeon HD 6790 has 320 fewer stream processors and the ones that it has left run 60Mhz slower than the AMD Radeon HD 6870. As you can see both the core and memory clock speeds on the AMD Radeon HD 6790 are higher than what is seen on the AMD Radeon HD 6850.

Pictured above is the AMD Radeon HD 6790 graphics card that AMD sent out and if it looks familiar to you don't be surprised. The reference design that AMD sent out is identical to the AMD Radeon HD 6870. It's the same exact PCB and cooler that is used on the Radeon HD 6870! We asked AMD about this and they said that the cards on the market won't look like this:

Though the reference boards we sent out to you may resemble the 6870, the AIB designs will vary greatly from what you’re seeing on our sample boards, including PCB, power connectors, cooler design etc. This means the AIBs have the choice to, e.g. include one or two power connectors on the PCB. - AMD Marketing

Since AMD said that retail cards won't be based on this design it means that our performance numbers should represent what you see on the store shelves, but the power consumption, temperature testing and overclocking results will greatly vary.