Realistically though, this is kind of like comparing a brand new apple with a dependable orange – AMD can bank on the performance of the 7nm node because they know exactly how to squeeze all of the power from a node that size, whereas Nvidia is looking to expand their horizons with new tech. On paper, there isn’t that much difference and it shouldn’t sway your choice too much.
We can also talk about performance per watt and power requirements if you like – cards at this price point are definitely going to be greedy when it comes to power…or so you would think.
In reality, the 6900XT will only require 300W of power running to it for optimal performance, and even then AMD has been very vocal about how RDNA2 and the whole of the Big Navi generation has been created with a focus on pushing the performance per watt of each of the cards featured in the range – in fact, within the 6900Xt, you can expect a 65 percent increase in the performance-per-watt compared to that seen in previous generation RDNA cards – which is pretty amazing.
On the other hand, though, you have the RTX 3090, which is a little needier when it comes to power. In fact, it needs 350W for a steady power supply, and even then there are plenty of reports of this card being quite thirsty when it comes to its general running, with some users reporting that its performance-per-watt can vary greatly depending on the actual tasking of the graphics card itself. If we are talking actual benchmarks, then the 3090 lies at the top of the most power-hungry graphics cards on the market today, delivering .25FPS per watt but also needing the most juice to keep running.
Now, there is one area when it comes to posted specifications where we can pick a clear winner out of these two cards – and that’s the size of them. It’s no secret that the BFGPU, the 3090 is the larger of the two cards, with the card demanding triple slot capabilities and measuring out at 310mm – not small by any stretch, and it could cause a problem for those looking to build a gaming PC in smaller cases.
The Radeon RX 6900XT on the other hand is no bigger than its less powerful 6800 XT relative, 267mm long with a triple-slot cooling solution – so noticeable smaller. That surface area translates to a less noticeable noise level and temperature in the 6900 XT as well – with a 10% lower fan noise, and a 4% lower maximum recording temperature. So, if those factors are important to you, you now know that the 6900 XT isn’t just the smaller card, but the one that stays cooler.
When it comes to judging these two graphics cards though, we really do have to look at them as a sum of their parts, rather than examining each individual component. So, for that, let’s look at the performance of the Radeon RX 6900XT versus the GeForce RTX 3090.