PowerColor Red Devil Ultimate Radeon RX 6900 XT Review: Speed Demon

We also spent some time overclocking the PowerColor Red Devil Ultimate Radeon RX 6900 XT using the various performance and tuning tools built into AMD's Adrenaline Edition driver suite. Like other Radeons, when the GPU powering this card is boosting, frequencies and voltages dynamically scale up or down, based on the GPU's workload and its thermal and power thresholds at the time. That frequency and voltage curve, however, can be altered to increase performance, save power, or sometimes both.

With the tuning options built into AMD's driver suite, users have multiple ways to tweak a Radeon RX 6900 XT's performance. Users can manually alter frequencies, memory timings, voltages, fan speeds, and the max power target using percentages or finer-grained numerical sliders, or they can opt to use various preset modes or auto-tune a number of characteristics, including GPU and memory frequencies, as well as GPU voltage, including under-volting.


With GPUs, like the Navi 21-based Radeon RX 6900 XT, AMD has incorporated a network of thermal sensors across the die to best ascertain its overall operating temperature. Data gathered from the sensors is used to determine what AMD calls the "Junction Temperature", and it's this Junction Temperature that is used to tune the card's power and thermal profiles (the Junction Temperature is effectively the hottest part of the GPU die at any given time). AMD claims the resolution and accuracy from the multiple thermal sensors allows it to increase overall sustained performance, because throttling based on the Junction Temperature is more reliable and effective than older methods.

The tuning options built into AMD's Radeon Software suite offer manual controls, along with automatic under-volting and automatic GPU and Memory overclocking. Finding the highest stable memory and GPU clocks, at the lowest voltage possible, while simultaneously increasing the max power target and keeping temperatures low, will yield the best overall overclocking results. If you'd rather not muck around though, you could simply enable Rage Mode, which essentially increases the power target and fan speeds, to increase the average game / boost clocks, and eek out a bit of extra performance. And with cards like the PowerColor Red Devil Ultimate Radeon RX 6900 XT that have a specially binned GPU, AMD has already tweaked some of those limits.


At its stock settings, we saw the GPU clock typically hovering in the 2,500 - 2,580MHz range while gaming (give or take) with our particular PowerColor Red Devil Ultimate Radeon RX 6900 XT sample. And with a little tweaking we found that we could easily max-out the memory clock on our card to 2,190MHz (17.5Gbps) with Fast memory timings enabled. With a mild under-volt to 1,175mV on the GPU, a max frequency set to 2,649MHz, and +15% to the power target, we typically saw a wider-range of real-world game clocks, commonly in the 2,550MHz - 2,640MHz range, though it occasionally spiked higher. The junction temperature while overclocked peaked in the low 80°C range with these settings, with a bump to the fan curve into the 2,700-ish RPM range.


While we had the card overclocked we saw a decent performance uplift. We also tested Rage Mode with the card to see how it affected performance, without having to manually muck with anything. Considering how high PowerColor had already configured the Red Devil Ultimate Radeon RX 6900 XT's clocks, we weren't expecting to be able to push things too much further, but were still able to achieve another ~3+% increase, depending on the title being tested, which was enough to push the card into the lead in FarCry New Dawn, overtaking the GeForce RTX 3090. 

Total System Power Consumption Tested at the Outlet

PowerColor Red Devil Ultimate Radeon RX 6900 XT Review Summary

The PowerColor Red Devil Ultimate Radeon RX 6900 XT is an absolute beast of a graphics card that hits a number of high notes. The card has a highly capable cooler that helps keep temperatures in check, even with its significantly higher clocks than AMD's reference design and its higher power limit. The PowerColor Red Devil Ultimate Radeon RX 6900 XT also has a bunch of cool features, like addressable RGB lighting, lighted ports, and a user-selectable BIOS switch for toggling between a high-performance OC mode or a lower-power (but still fast) Silent mode. The shroud and backplate are metal, which gives the card solid rigidity, and if you want to give it even more support and alleviate stress on your PCI Express slot, PowerColor has you covered there as well, thanks to the included support bracket.

PowerColor Red Devil Ultimate Radeon RX 6900 XT Cards @ Amazon.com

If you're OK with the gargantuan physical dimensions and higher power of the PowerColor Red Devil Ultimate Radeon RX 6900 XT, it's arguably one of the fastest graphics cards on the market today for traditional rasterization (but not when ray tracing). But you're probably wondering what all that means in terms of cost. Unfortunately, we can't give a clear answer at this point.

In addition to the current market craziness due to supply shortages and the increased demand for GPUs from miners that has driven GPU prices through the roof, PowerColor didn't provide any MSRP for the card. If it has an MSRP that was only mildly higher than reference Radeon RX 6900 XTs, we would recommend the PowerColor Red Devil Ultimate Radeon RX 6900 XT in a heartbeat for anyone looking for a graphics card in this class. But if we're talking hundreds of additional dollars for a few additional percentage points of performance and more overlocking flexibility though, it becomes tougher to recommend. We'll just have to wait and see how things shake out once we can get a gauge of actual street prices, which isn't going to be anytime soon unfortunately. On its performance and design merits alone though, the PowerColor Red Devil Ultimate Radeon RX 6900 XT kicks some serious tail and it was one heck of a fun GPU to play with.

Killer Performance Higher Clocks And Power Limit Powerful Cooler Addressable RGB Lighting Lighted Ports	She's A BIG One! Unknown Pricing Limited Availability