Micron expects GDDR7 will improve ray tracing and rasterization performance by more than 30%, compared to previous gen VRAM

pcgamer.com:

RAM chip manufacturer Micron has recently been making some interesting claims about its next generation of ultra-fast memory for graphics cards, GDDR7. Compared to what's currently being used (GDDR6X and GDDR6), Micron says its forthcoming tech is «expected to achieve greater than 30% improvement in frames per second for ray tracing and rasterization workloads.»

That's a remarkable performance boost, no matter how you look at it, and it's normally the preserve of the significant architectural changes a new GPU design brings in. However, while it's certainly true that the data transfer rate and bandwidth of GDDR7 will be at least 30% greater than the fastest GDDR6/6X on offer right now, it's a different story altogether when it comes to actual games and applications.

Micron supplies all the GDDR6X chips used in Nvidia's graphics cards and the fastest it offers is rated to 24 GT/s (24 billion transfers per second). It also sells 18 GT/s GDDR6, though Samsung has 20 GT/s GDDR6 for sale. When it comes to GDDR7, though, only Micron is providing any specifications at the moment and the two models available for sampling are rated at 28 and 32 MT/s.

Take 24, increase it by 30%, and you get a value of 31.2 so it's obvious where Micron is getting its performance claims from. But let's say you could take that GDDR7 and add it to a current graphics card (ignoring the fact that it actually wouldn't work because the GPU can't use it)—would games and benchmarks be 30% faster, like Micron says?

I ran through a few tests on an RTX 4080 Super, changing the clocks on its VRAM across the widest range I could manage. Everything else remained the same, the performance differences visible are purely from altering the memory clocks. First up were two 3DMark tests, Steel Nomad and Speed Way. The former uses traditional rasterisation techniques for all the graphics, whereas the latter shoehorns in a fair amount of ray tracing.

It wasn't possible to achieve a 30% difference in clock speeds