PowerColor Hellhound Radeon RX 7900 XTX Spectral White Review
PowerColor Hellhound RX 7900 XTX: Overclocking, Power, Noise And The Verdict
While new RDNA 3-based Radeons have de-coupled front end and shader clocks, which may seem to complicate things, the two clock domains are linked, so the actual overclocking process is similar to previous-gen cards.
The tuning options built into AMD's driver suite give users the ability to manually alter frequencies, voltages, fan speeds, and the max power target, using percentages or finer-grained numerical sliders. Users can also opt to use various preset modes or auto-tune a number of characteristics, including GPU and memory frequencies as well as the GPU voltage, including under-volting.
With older Radeons, a single sensor had been used to determine the GPU temperature, and data from that lone sensor was used to control the card's thermal profile. With newer RDNA 2 and RDNA 3 GPUs, like the Navi 31 powering the PowerColor Hellhound RX 7900 XTX, AMD has incorporated a network of multiple thermal sensors at strategic locations across the die. Data gathered from the sensors is used to determine what AMD calls the "Junction Temperature", and it's the 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).
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, is what will yield the best overall overclocking results. If you'd rather not mess around though, you could simply enable Rage Mode, which essentially increases the power target and fan speeds, to effectively increase the game / boost clocks, and squeeze out a bit of extra performance with a single-click.
At its stock settings, we saw the PowerColor Hellhound RX 7900 XTX's GPU clock typically hovering in the 2,600 - 2,700MHz range while gaming (give or take) with our particular sample, with a junction temperature in the mid-80s. With some tweaking we found that we could easily increase the memory clock on our card to 2,642MHz (21.1Gbps, effective), and with a mild under-volt to 1.130mV, a max frequency set to 3,030MHz, and +15% to the power target, we typically saw a wider-range of real-world game clocks, commonly in the 2,700MHz - 2,830MHz range. The junction temperature while overclocked peaked in the mid 90°C range with these settings, without modifying the default fan curve. The cooling setup on this card does a nice job keeping temperatures in check without making much noise, but bumping up the fan speed would be advisable to bring that junction temperature down a bit.
While we had the card overclocked, we re-ran a couple of tests and realized some decent performance gains. In both 3DMark Time Spy and FarCry 6 (using RT), overclocking the PowerColor Hellhound RX 7900 XTX's performance increased measurably and inched closer to the GeForce RTX 4090. In FC6, the two cards actually put up the same average framerate with RT enabled at 4K.
Total System Power Consumption TestingWe'd also like to cover a couple of final data points regarding power consumption and acoustics before we wrap up. Throughout all of our benchmarking and testing, we monitored noise output and tracked how much power the test system was consuming using a power meter. Our goal was to give you an idea as to how much power each GPU used while idle and also while under a heavy workload. These power numbers were captured during a FarCry 6 4K benchmark run with ray tracing enabled...
In terms of noise output, the PowerColor Hellhound RX 7900 XTX is relatively tame when running at stock settings. The cards' fans completely stop at idle, so it if effectively silent. Under load, the fans typically hovered around 1,200 RPM under long sustained loads, which produced a dull, deep whir that wasn't particularly noticeable over our test system's PSU fans and CPU cooler. Overall, the PowerColor Hellhound RX 7900 XTX is relatively quiet in comparison to other high-end GPUs in this class.
PowerColor Hellhound RX 7900 XTX Performance And Review Summary
Stepping back and looking at its specifications and benchmark results alone, the PowerColor Hellhound RX 7900 XTX Spectral White doesn’t seem all that different from other Radeon RX 7900 XTX cards. Its GPU clocks are within 1% of AMD’s design, with the same memory configuration and GPU features. The Hellhound, however, has a larger cooling solution and a completely different design language, which manages temperatures well while also keeping the card quiet, even under load (it’s dead silent at idle).
The capable cooling solution on the PowerColor Hellhound RX 7900 XTX Spectral White also allowed for some decent overclocking, with minimal effort. With some additional tweaking, we suspect this card could be taken even further, especially if you’re comfortable increasing fan speeds a bit to get that junction temperature down.
All told, the PowerColor Hellhound RX 7900 XTX Spectral White is an excellent GPU and may be exactly what the doctor ordered if you’re looking to build an all-white, Radeon-based gaming rig. It’s fast, quiet, and looks the part. We couldn’t find the PowerColor Hellhound RX 7900 XTX Spectral White available for sale just yet, but PowerColor tells us to expect a small $20-30 premium for the white version. If a white Radeon RX 7900 XTX is the missing link to complete a build, check out the PowerColor Hellhound RX 7900 XTX Spectral White. This is a top-notch GPU.