AMD Radeon HD 6850 and 6870 CrossFire Video Card Review

The AMD Radeon HD 6850

The Radeon HD 6850 1GB GDDR5 is the first video card in the new
Radeon HD 6800 series that we will be showing you today. The Radeon HD
6800 series has a whole new look to it and while they
kept the red/black color scheme the ‘batmobile’ look of the Radeon HD
5800 series is long gone. This new card has what people are calling a wave motif as you can see from the picture above.

This video card measures 9″ long and is a dual-slot card with a squirrel cage type cooling fan on it.

The back of the Radeon HD 6850 is open and doesn’t have any of the
1GB GDDR5 memory visible on this side of the PCB. The only thing worth
noting here is the GPU support bracket that is also common on the
current generation of video cards.

Long ago we heard rumors that the Radeon HD 6800 series would be the
first video card to support the PCI Express 3.0 standard, but we haven’t
heard that rumor in many months and this card supports just PCI Express 2.1.

The 6-pin PCIe power connector on the AMD Radeon HD 6850 is located
at the end of the video card on the top corner. AMD says that a 500W or greater power supply is needed with at least one 75W 6-pin PCI Express power connector. For those that want to run two Radeon HD 6850 cards in CrossFireX you’ll need at least a 600W power supply and two 6-pin connectors. Since the card is only
9″ long, it still should still be able to fit in most of the cases on
the market today.

The AMD Radeon HD 6850 has a pair of mini-DisplayPort 1.2 connectors
on it that have double the data-rate of DisplayPort 1.1. In addition to
the higher data-rate, DP 1.2 also brings support for higher resolution
support and support for stereoscopic 3D. The new HD 6800 series supports up to six DisplayPort displays by “daisy
chaining” them to two Displayport outputs. To the right of the pair of
mini-DisplayPort connectors is a full size HDMI 1.4a output for 3D video
(Blu-ray 3D) support and dual-link DVI-I and single-link DVI-I outputs.

You can see that AMD has some ‘vents’ that are located along the top
edge of the Radeon HD 6850, but that isn’t for hot air from the cooling
fan. That air is contained within a red ‘tube’ that is exhausted out of
the case via the exhaust vent that can be seen on the PCI panel
bracket. Notice that the Radeon HD 5850 only has one CrossFire interconnect. This means that you’ll only be able to run two cards together and that triple or quad CrossFire is out of the question.

Taking the heat sink and fan cover we can see that a small copper heat sink and a 4-pin fan is used to cool the Radeon HD 6850. Also notice that the 1GB of GDDR5 memory chips have a heat spreader over them to help keep them cooler during use.

Here is a shot with the memory heat spreader removed. The cooling fan is by a company called FirstD and is a 0.7 Amp DC Brushless 12V model with part number FD9238M12D. The copper heat sink doesn’t have any heat pipes and is a

AMD is using Hynix branded GDDR5 ICs on their Radeon HD 6850 video card and the part number was H5G01H24AFR-T2C. These memory ICs are speed rated at 1250MHz or an effective clock speed of 5GHz. Since AMD has this card clocked at just 1000MHz it is likely these memory IC’s have room left in them to overclock!

We always get e-mails asking for something to be used to put things into size perspective, so here is a United States Quarter Dollar sitting next to the core. As you can see, the new die is about the same size as the quarter.

Here is a closer look so you can see the markings on the core itself. This one was made week 37 of 2010 and you can see that it was an engineering sample as it has ENG stamped laser etched onto it. These dies are made on the 40nm process by TSMC over in Taiwan.

XFX sent over their custom designed Radeon HD 6850 for review as well and we wanted to take a second and show you that card. XFX already has a custom designed PCB and cooling solution card on the market! This card has model number HD-687A-ZN and is about half an inch shorter than the AMD reference design. It also features a larger cooler with a huge heat-pipe on it for better heat dissipation. The card features the same clock speed as the AMD reference design and the performance was the same. Due to this we’ll be showing just one card in the performance benchmarks, but will be showing both the XFX and AMD cards in the power consumption and temperature testing as the cards do differ in those respects.

As you can see from the back of the card the PCB layout is totally different on these two cards, so no wonder we noticed a power and temperature difference! Since both cards are the same speed and model we will be running them together for CrossFire testing as well.

XFX also did something a little different with their display connectors and rather than offering two mini-DisplayPort 1.2 headers they opted to use a single full size DisplayPort connector. The also have their name cut into the exhaust bracket, which is a nice touch along with the red DVI connectors.