Tried it: AMD Radeon HD 7870/7850 - dangerous pit bulls

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ASUS HD 7870 TOP DirectCU II TOP (HD7870-DC2T-2GD5)

From the ASUS workshop, the manufacturer’s current most powerful Pitcairn model arrived in the person of the HD 7870 DirectCU II TOP. The side note of TOP is the guarantee that the engineers also performed a more serious factory tuning on the card, but let's not run so far ahead! VGA is based on a black printed circuit board (probably ASUS custom PCB with a length of 26,5 cm, a width of 11,4 cm and a height of 4,3 cm - along with cooling), on which the company is already well known for its own cooling, DirectCU II is resting, this time with the “thinner” two-slot version, with the usual two 8mm fans, of course with PWM control.

On the GPU, a thicker, less lamellar aluminum rib extends, from which three 6 mm copper heat pipes start toward the card’s tail, where the heat delivered is awaited by another, thinner and more densely laminated aluminum rib. All this is made possible by the usual stylish plastic cover with the usual ASUS branding and DirectCU marking. For power, two 6-pin PCI Express power connectors are sufficient, facing “up” in the corner at the end of the PCB.

Opposite them, on the other side, the CrossFireX connector rests and waits to find a partner for itself. The grid on the front panel runs the full width, with the outputs below, which means a dual-link DVI, a native HDMI and two mini Displayports. We’re beyond the technology description, which means we now know that the 7870 cards come with 2GB of GDDR5 on board as standard. The reference clock is 1000 MHz for the GPU and 4800 MHz for the RAM (1200 MHz).

In comparison, the TOP version of the ASUS received a 100 MHz clock boost for the GPU and a 200 MHz clock boost for the memories, the operating frequencies of the TOP version being 1100/5000 MHz. The GDDR5 chips are Hynix H5GQ2H24MFR-T2C specimens, i.e. in principle they are set to their maximum performance. The box still boasts the usual Radeonos ASUS colors and design, in addition to the card you will find the usual things: installation disc, manual, PCI Express power converter, dsub-VGA converter, CrossFireX bridge.

ASUS HD 7850 DirectCU II TOP (HD7850-DC2T-2GD5)

Let's get to know the little salt for the first time in the motherhood of ASUS! At first, the HD 7850 would be thought of as twin brothers with his brother, but it soon turns out the appearance is cheating. The deception is caused by the DirectCU II cooling, which is exactly the same piece as the one on the 7870 TOP, i.e. the dimensions are the same. However, if we look closer behind it, we can see that the black printed circuit board is significantly shortened, only 20 cm long. 

In connection with the installation, however, it is worth calculating the dimensions of the 7870 TOP due to the cooling. Because the cooler extends significantly beyond the PCB and the one-piece 6-pin PCI Express power connector also faces rearward, ASUS has solved the issue with a cable extension to make the power connector interface easily accessible. On the other side, we also get a CrossFireX bridge to build a connection between two cards.

The GDDR5 chips are also on the GPU side here, with a total capacity of 2GB, and this time the Hynix H5GQ2H24MFR-T2C was the runner-up. AMD's recommendations for the 7850 are 860/4800 MHz, which means that there isn't much spare space left in the RAMs either (in theory, this chip is certified for 5 GHz), especially since ASUS, being a TOP version, has a GPU clock of 975 MHz. while increasing its RAM to 5000 MHz. This, of course, is just a pleasure for customers, as they also have a significant amount of factory overdrive here, which is immediately ready for use and we don’t have to experiment. 

The back panel design and outputs are unchanged from the big brother, meaning we get a dual-link DVI, a native HDMI and two mini Displayports. We can only repeat ourselves about the contents of the box: installation disc, manual, PCI Express power converter, dsub-VGA converter, CrossFireX bridge.