Review: Nvidia GeForce RTX 3080 Founders Edition

GA102 as GeForce RTX 3080

Here are the GeForce RTX 30-series GPUs laid bare next to their 20-series brethren. We're focussing on the RTX 3080 in particular. Like the RTX 3090, it uses the 28.3-billion transistor GA102 die that, if you recall, comprises 84 SMs across split across seven GPCs, and you see it in all its floorplan glory on the previous page.

The RTX 3080 implementation removes one GPC and further trims two others to hold 10 instead of the maximum 12 SMs. That means a total of 68 SMs (4x12 plus 2x10). The resultant core calculations are straightforward. RTX 3080 holds 8,704 cores that look so impressive compared to the paltry 3,072 on RTX 2080 Super, which is the GPU it effectively replaces at the $699 price point.

But do recall just how these cores are counted. Half of the them are straight-up FP32, while the other half can do FP32. Unlike Turing there is no further, dedicated INT pipe. Even so, Nvidia is correct in saying that at a peak boost speed of 1,710MHz RTX 3080 has nearly 30 TFLOPS of raw FP32 power, compared to 11.1 on RTX 2080 Super. This is fantastic if your GPGPU workloads smash out FPs, where RTX 3080 is a monster, but less relevant in gaming.

Even though RTX 3080 has more SMs than RTX 2080 Super - 68 vs. 48 - it has fewer Tensor cores due to there being half as many in every SM. There's no such reduction in RT cores, however, so they remain aligned to SMs on a 1:1 basis. ROPs, however, see a hearty increase due to them being decoupled from the backend and located in the GPC instead.

SLI goes by the wayside on this model, with Nvidia increasingly moving away from it on anything but its best-in-class GPU, and keeping up with interfaces, PCIe 4.0 is present and accounted for here

Nvidia increases the memory footprint to 10GB and, as discussed ramps up bandwidth by using GDDR6X operating at 19Gbps on, this time around, a 320-bit bus. Frequency and width combine to offer 760GB/s of bandwidth, or 53 percent more than its direct predecessor.

The visceral numbers suggest that not only is RTX 3080 far quicker than RTX 2080 Super - up to twice as fast, if you believe Nvidia's best-case projections - it ought to be substantially quicker than RTX 2080 Ti, which is a GPU that cost almost twice as much on its release two years ago.

Benchmark performance is likely not in doubt because it will top the charts compared to the existing competition. We're more concerned with the 320W TDP. Nvidia, too, realises that it needs innovation to cool such densely-packed heat. Enter the all-new Founders Edition card.