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Its Tahiti TX GPU was manufactured in Taiwan. We couldn’t read the manufacturing date from the barely visible marking.

The GPU has a standard Tahiti TX configuration you can see in the specs table. As we’ve said above, the two BIOS versions have GPU clock rates of 1070 and 925 MHz at the same voltage of 1.175 volts. The quality of our sample is rather low at 65.5%:

The card carries 3 gigabytes of GDDR5 memory in 12 FCBGA-packaged chips from Hynix Semiconductor labeled H5GQ2H24MFR R0C:

The two BIOS versions differ in graphics memory clock rate: 5500 and 5600 MHz. Considering that memory can be easily clocked at higher frequencies on top-end AMD and Nvidia cards, MSI could have written 6000 or even 6400 MHz into the faster BIOS version. On the other hand, memory frequency doesn’t contribute much to the overall performance of a Radeon HD 79xx card.

So, here are the MSI R7970 Lightning specs with the slower BIOS version selected:

With the faster BIOS version, the MSI R7970 Lightning becomes one of the fastest serially manufactured Radeon HD 7970s:

The MSI Twin Frozr IV cooler is just as exciting as the graphics card itself:

Like its previous versions, the fourth Twin Frozr has a nickel-plated aluminum heatsink with copper heat pipes, two fans and a casing:

There are five heat pipes here: the two outermost ones are 8 millimeters and the three others are 6 millimeters in diameter.

The pipes are soldered to both the cooler’s base and fins.

The power system components and memory chips are cooled by a steel plate with thermal pads. The metallic plate on the reverse side of the PCB has no contact with any components and seems to be nothing but decoration. It may also serve a protective function.

The fourth version of the Twin Frozr cooler features larger fans which are 100 rather than 92 millimeters in diameter:

The fans are manufactured by Power Logic (the PLA10015B12H model with dual ball bearing). The speed of the fans is PWM-regulated within a range of 1100 to 3300 RPM. Like in the previous versions of the Twin Frozr, the innovative design of the 11-blade impeller helps generate 20% stronger air flow compared to classic impellers. The cooler has a cleaning feature: after turning off, the fans rotate for about 30 seconds in the opposite direction to exhaust dust from the heatsink. Each fan is equipped with blue highlighting.

Here is the temperature of the card with its fans regulated automatically:


925 / 5500 MHz

1070 / 5600 MHz

At the standard GPU clock rate of Radeon HD 7970, the GPU temperature of the MSI R7970 Lightning is 69°C and its fans rotate at 2260 RPM. Its VRM is 54°C and its memory is 57°C hot then. At a GPU clock rate of 1070 MHz the GPU and memory are 72 and 60°C hot, respectively, while the VRM temperature remains the same and the fans rotate at 2660 RPM. The Twin Frozr IV cooler is evidently efficient, especially with the power system components.

The graphics card didn’t get much colder at the maximum speed of the fans. The temperatures lowered by only 3-5°C:


925 / 5500 MHz

1070 / 5600 MHz

Despite the low ASIC Quality of the GPU of our sample of the card, we could overclock it to 1165 MHz at the standard voltage of 1.175 volts.

We couldn’t increase the GPU clock rate more at 1.25 or 1.3 volts. The card could pass tests even at 1250 MHz, but produced a lot of visual artifacts, so we rolled back to 1165 MHz. The memory chips were stable at 7160 MHz. We then took the GPU Reactor off and reached a GPU clock rate of 1140 MHz, which was a mere 25 MHz lower than with the GPU Reactor installed. The latter didn’t affect the overclocking potential of the memory chips.

Overclocked to 1165/7160 MHz, the graphics card had the same temperature but its fans almost reached their maximum speed:

So, the MSI programmers seem to have set too high limits for the speed of the fans. The fans could be made quieter at the expense of a few degrees of GPU, VRM and memory temperature which would anyway remain lower than 80°C as is perfectly normal for today’s top-end graphics cards.

 
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