Gamers Nexus: AMD Vega Hybrid Mod, Overclocking and Power Leakage Explored

Having acquired the latest and (perhaps) greatest graphics card from AMD, the Vega: Frontier Edition, Steve Burke and his colleagues at Gamers Nexus decided to explore the performance parameters of the new card and indeed the new Vega architecture GPUs. They started by adding a closed loop cooler (CLC) to the card, a job which ended being quite a mission due to the slightly irregular mounting holes on the PCB. The problem was eventually solved by using an old Intel CPU mounting bracket and creating some 64mm x 64mm retention holes. You can find the entire ‘Hybrid Mod’ Build Log video here. The Hybrid mod also added some small finned heatsinks to the VRM components to further eliminate thermal issues.

The idea behind the hybrid mod is that it’s not just about being able to get more performance, it’s also about finding the thermal limitations of the card / GPU and how these thermals relate to fan speeds and ambient noise levels. It also allows Steve and his team to gain a bigger picture about the card in terms of overclocking headroom and issues like power leakage. Here’s a sample of what they discovered:

The Vega FE Hybrid mod posted reasonable gains in overclocking over the air-cooled counterpart, something we originally thought was due to more aggressive clock scaling at lower temperatures – similar to what’s seen on Pascal. We later learned it was to do with power leakage and power limitations on the GPU, as we’ll dig into momentarily. We were able to max-out our stock card overclock at around 1660MHz with an 1100MHz HBM2 OC, which we ultimately found to govern performance gains most heavily.

The Hybrid card, with the help of some fans pointed at the VRM components, was able to overclock to 1705MHz completely stable, with an 1105MHz HBM2 OC. We ended up running all our tests at 1700/1100 for now, but will be revisiting with slightly higher clocks later. The VRM fans proved unnecessary after more testing, but we’ll get to that momentarily.

Pushing to 1710MHz resulted in a near-instant crash, and measuring at the PCIe cables shows that this is when power throttling begins to occur with greater frequency (causing the instability and subsequent crash). We’re hoping to attempt some BIOS mods – no promises – to increase TDP. Just depends on what tools are made available to us, or what we can figure out through external tools.

You can find the full Hybrid Mod article from Gamers Nexus here, as well as the video that Steve posted on their YouTube channel here. It’s great see that fairly mainstream tech site is willing to conduct these kinds of experiments to delve deeper in to the actual technology that powers today’s 3D gaming titles. It’s also great to see that his video on the topic currently has almost 50,000 views and almost 500 comments. Nice work guys!

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