Memory bandwidth in the Series X seems to be a problem.
All those FLOPS, but a bottleneck on the way in and out of the APU makes things perform like shit.
Digital Foundry Wild Hearts Tech Analysis
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All those FLOPS, but a bottleneck on the way in and out of the APU makes things perform like shit.
3? It's not even 2. And as many said... The PS5 has the better engineering. It's not jus the SSD. The whole IO is designed to limit bottlenecks. Series X has a bottleneck straight into their ram configuration, another one from having too big shader arrays...
People keep remembering Series X bandwidth split but I think there are more serious design flaws that can make it less efficient… for example the Compute Units (CUs).
1) Disproportional number of CUs… 14CUs per Shader Array… that was s something AMD never did before and always focused on the 10CUs per Shader Array for optimal performance… PS5 had 9 CUs per Shader Array.
2) Disproportional L2 cache… It has 5MB total L2 cache for 56CUs… that is ~0.09MB per CU… typical RDNA/RDNA2 has 0.1MB or more per CU… PS5 has 0.11MB per CU.
3) Disproportional bandwidth… even taking only the fast RAM as usable (games that require less than 10GB of RAM)… Series X has a bandwidth of 10GB/s per CU… AMD cards have way more than that (15-18GB/s) and PS5 has 12.45GB/s per CU.
I only focused in CUs here but these 3 point show a clear bootleneck in efficiency… for example if some CU requires more than 10GB/s of bandwidth others CUs will have to hold doing nothing because there is no data reaching to be processed… same for weird Shader Array and the limited L2 cache.
And I’m not even talking about the others parts of GPU… just focusing in the compute part (CUs).
These 12TFs have serious hardware bottlenecks to be fully used… in most cases Series X will have CUs doing nothing because the others parts can’t feed them fast enough.
1) Disproportional number of CUs… 14CUs per Shader Array… that was s something AMD never did before and always focused on the 10CUs per Shader Array for optimal performance… PS5 had 9 CUs per Shader Array.
2) Disproportional L2 cache… It has 5MB total L2 cache for 56CUs… that is ~0.09MB per CU… typical RDNA/RDNA2 has 0.1MB or more per CU… PS5 has 0.11MB per CU.
3) Disproportional bandwidth… even taking only the fast RAM as usable (games that require less than 10GB of RAM)… Series X has a bandwidth of 10GB/s per CU… AMD cards have way more than that (15-18GB/s) and PS5 has 12.45GB/s per CU.
I only focused in CUs here but these 3 point show a clear bootleneck in efficiency… for example if some CU requires more than 10GB/s of bandwidth others CUs will have to hold doing nothing because there is no data reaching to be processed… same for weird Shader Array and the limited L2 cache.
And I’m not even talking about the others parts of GPU… just focusing in the compute part (CUs).
These 12TFs have serious hardware bottlenecks to be fully used… in most cases Series X will have CUs doing nothing because the others parts can’t feed them fast enough.
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Called it a while back on here, almost a year ago on other forums; the Series X has a big problem. The shortfalls of the S we all saw coming a mile away. The X is fucked.
I like using the original '9tf' quote when comparing the ps5 to the XSX. Just to really hammer home how poorly the X is doing in terms of performance on paper. I know it's petty, but I was griefed on gaf for stating that the 10.2 wasn't a last minute design.
Cerny knew the bottlenecks and IO would be a priority this gen, because the devs he asked told him so. I guess no one at Microsoft cared to ask their devs what they wanted.
I'll bet a lifetime ban that there's a Series X revision in the works as we speak. We may even hear about it at E3.
MS doesn’t ask its partners anything, ever. It dictates to them and let’s them deal with the fallout.
Well, to be honest a good number of people use the release date to decide if a console is "next gen".
By that yardstick, every console launched since 1987 is a Next Generation console…Well, to be honest a good number of people use the release date to decide if a console is "next gen".
