AMD did a good job with their Radeon HD 7870. MSI's HD 7870 HAWK builds on that foundation and tries to create an overclocker's SKU that provides maximum performance and overclocking potential.
Thanks to the 100 MHz overclock out of the box, the HD 7870 HAWK has a 5% performance advantage over the AMD reference design. This is a decent increase, yet I would have expected more from a card like this, as there is plenty of clock headroom available. MSI's Lightning gains 8% over the respective reference design. Our manual overclocking tests confirmed that the HD 7870 HAWK overclocks very well. A maximum clock of 1260 MHz is the highest GPU clock we have ever seen in a TPU review, and is only matched by the ASUS HD 7870 Direct CU II. MSI has also included the dual BIOS feature, which is used to enable a special liquid nitrogen optimized BIOS. We also see the voltage measurement points on the card that we like so much. On the back of the card an extra PCB "GPU Reactor" has been added. It provides additional filtering for the GPU voltage, but I wonder why this couldn't have been more integrated into the PCB, so it doesn't take up extra space, which might make multi-GPU configurations difficult in small cases.
Power consumption during typical gaming is slightly increased, due to the higher clocks. Furmark shows a large increase of 100 W over the reference design though. I have to admit, Furmark is not a realistic test for every day usage, but it can still provide an additional data point, for worst-case scenarios for example. Such a large increase in power consumption is very uncommon. We have seen similar results on the ASUS HD 7870 DC II, on the other hand MSI's HD 7870 Twin Frozr II shows no such power increase. While I can't provide a definitive explanation, I suspect that power consumption of AMD's Pitcairn GPU varies wildly between individual batches.
Another thing I didn't like was the excess noise coming from the card once it got heavily stressed. With 49 dBA it is one of the noisiest cards we've tested for a while. This seems to be closely related to the high power consumption, which produces tons of heat, that has to go somewhere to keep the card cool. Temperatures in idle are comfortably cool, and perfectly safe under load (76°C).
MSI has not communicated any final pricing for the HD 7870 HAWK, but given that the HD 7870 Twin Frozr II retails at $370 and the HAWK is supposed to be a step up from that, I'd expect it to be somewhere around $380 which is clearly too high. ASUS offers their HD 7870 Direct CU II at the reference design price of $360, and it comes with the same GPU clock as the MSI HD 7870 HAWK, and 50 MHz higher memory, but less OC features. So that would be a reasonable price for MSI to consider.