Conclusion
We have now fully reviewed the AMD Radeon RX 6900 XT and overclocked it in this review. We have looked at 1440p performance, 4K performance, Ray Tracing performance, and FSR performance.
The AMD Radeon RX 6900 XT is currently AMD’s flagship video card with an MSRP of $699. This is $350 MSRP above the Radeon RX 6800 XT. The primary difference between the two is that the Radeon RX 6900 XT has 80 Compute Units versus the Radeon RX 6800 XT’s 72. This means 5,120 Stream Processors versus 4,608. The game clock and boost clock remain the same between the video cards, and they both have 16GB of VRAM at the same frequency.
In our full review, we found that the AMD Radeon RX 6900 XT was only about 6-10% faster, at best, compared to the Radeon RX 6800 XT. It did not offer a large enough performance uplift for that $350 MSRP difference to make sense. It didn’t offer anything unique compared to the RX 6800 XT. We wondered if overclocking would be the key to unlocking its potential and providing enough of a value over the Radeon RX 6800 XT. In this article, that is exactly what we did.
Overclocking
Overclocking the AMD Radeon RX 6900 XT was not very difficult. We were able to utilize AMD’s Radeon Software and its manual performance tuning tab. It had all the controls we needed to overclock and allowed us to overclock everything but the voltage. The voltage was not unlocked.
We were able to raise the Power Limit by 15% which gave us a little playroom, but we did wish we had more. We also found that the memory overclock was limited and locked, which is not uncommon with built-by AMD video cards. The memory was locked to just 2150MHz (17.2GHz) versus the default 2000MHz (16GHz) frequency. Therefore overclocking the memory was very easy as we just maxed it out, and it worked. There is probably more headroom there, but we were limited in that way.
We then were able to turn the fan speed up and raise the GPU frequency as far as it could go stably. We found that to be around the 2720MHz mark on the slider. This resulted in the actual game frequency falling around the 2400-2450MHz range while gaming. The actual average overclocked was 2437MHz which is a 7% overclock from the default of 2286MHz average.
Generally speaking, the GPU clock speed is what is holding the Radeon RX 6900 XT’s performance back. It cannot clock as high as the Radeon RX 6700 XT or even 6800 or 6800 XT. This is due to its larger size. It cannot reach anywhere near the frequency of the smaller die-sized Radeon RX 6600 XT. This lower clock speed does hold back from what could be a much higher performing GPU, and of course, power eating GPU as well. That’s just the nature of it being densely packed with the full 80 Compute Units.
Performance
We did get a performance uplift in every scenario with the AMD Radeon RX 6900 XT by overclocking it. The uplift was about what the difference was from the Radeon RX 6800 XT to the Radeon RX 6900 XT. We saw around a 6-10% performance uplift in games, with and without Ray Tracing. The overclock allowed it to compete better with the GeForce RTX 3090.
There were many scenarios where it was now on par with the GeForce RTX 3090 where it was slower without the overclock. There were also scenarios where it was just slightly edging out the RTX 3090. There were no scenarios where it was significantly faster, however. There were also no scenarios where overclocking made Ray Tracing playable where it was not before. There were some scenarios where overclocking made gameplay smoother though, above 60FPS at 4K for example, which was welcomed.
Compared to the Radeon RX 6800 XT the overclocked Radeon RX 6900 XT was 10+% faster, we saw 12, 13, and even 15% faster performance compared to the Radeon RX 6800 XT. This is the kind of difference we wish had existed between them though without the overclock. That’s the kind of difference we wanted to see sans overclocking, to begin with. That kind of performance difference would have made the RX 6900 XT make sense over the RX 6800 XT. We could only get there though, by overclocking.
Final Points
Overclocking the AMD Radeon RX 6900 XT was not difficult, but it didn’t quite overclock as high as we would have liked. We understand why of course, it’s a large die, and densely packed with the full 80 Compute Units. Ultimately the lower frequencies hold it back, but we are pushing it to the extreme as it is. Perhaps custom add-in-board partner video cards could be pushed a little farther, but you will be eating a lot of juice to get there.
In the end, the $999 MSRP price tag compared to the $649 MSRP Radeon RX 6800 XT doesn’t make a lot of sense. If you plan to push it as much as possible overclocking it, the performance difference won’t be worth the price difference. But if you do plan to overclock it, it might make more sense. It might also make more sense over a GeForce RTX 3090 if it is cheaper, as that is more expensive by MSRP.