XFX 7900 XTX Merc 310 Graphics Card Review

Clock Speeds

Ok, so there’s a small uplift in performance around 4% in a small selection of games, but at what cost? Well, the XFX Merc 310 will set you back another 10% over an MSRP based card like the AMD reference or PowerColor Hellhound Skus, cementing itself at $1099, but it’s not as clear cut as that, because there’s other metrics to factor in, such as cooling and with this being such a large card with a pretty serious cooling solution, I’m expecting good things.

What we found during a run of F1 21 was the GPU temperature sitting around 54 degrees, which is dramatically lower than the 66 degrees we saw on both the AMD reference and PowerColor cards. Not stopping there, but the memory junction temperature also came in cooler by around 10 degrees at 80 degrees and the hotspot also remained in check at 72 degrees, which is a whopping 20 degrees lower than the other 7900 XTX cards that we’ve tested. During this, the GPU clock managed to get to around 2550MHz at 100% usage while the total board power remained around 390 Watts with the fans hovering around 1600 RPM.

So with a GPU that’s able to be so cool during stock operation, you’d like to think that overclocking would be pretty plentiful due to the headroom that’s available, but with the 7900 XTX and RDNA 3 as a whole, it’s not quite as clear cut due to the way that power is harnessed and what that means for pushing it to its limits.

Throughout our own testing, we actually found the best thing to do is to raise the power limit, put a small overclock on the memory and undervolt the card to maintain stability. Raising the boost clock range didn’t seem to garner much performance if any, and in some cases saw performance worsen due to extra heat that’s added and it’s the same for the memory.

With that in mind, we pushed the power limit to the max, undervolted the card by around 50mV and increased the core clock max frequency by 75MHz and the memory clock by around 100MHz to get the best balance between performance, and stability and this was pretty much a similar story with the previous generation of AMD cards too.

What this resulted in, at least in terms of cooling performance was a 4-degree increase, now up to 58 degrees on the GPU temperature, while the memory junction temperature increased to around 86 degrees, which both temperatures are still cooler than the other 7900 XTX cards that we’ve looked at. The Hotspot did increase but was still under control at 79 degrees, which was still dramatically less than again, what we had seen on other cards. Clock speed-wise, there were moments where we found it rising above 2800MHz during an extended level of gameplay at 100% GPU utilization. Due to the increased power limits, the total board power was now coming out around the 450 Watt mark, while the fans remained around the same, at 1600 RPM.

What this means in games is that in Call Of Duty Modern Warfare II we see just under a 9% uplift in performance in the averages and just over 9% in the 1% lows which is pretty impressive considering the temperatures were still well under control.

In Cyberpunk, the gain from overclocking was much smaller at just under 2% in the averages, while the 1% lows actually dropped by 2 frames per second, likely due to the extra heat not allowing the same level of boost for a sustained amount of time.

Death Stranding saw a healthy improvement of 4% in the averages which also led to a 5% increase over the AMD reference card. The 1% lows also see an increase of just under 2% but at such a high frame rate, it’s nothing you’d ever notice.

Lastly in Watch Dogs Legion, we saw a similar 4% uplift when overclocking in the averages, and a slightly healthier 5% increase in the 1% lows, now putting the XFX card 9% faster than the AMD reference card, which also had higher temperatures under stock operation.