View Single Post
Old 2020-07-25, 09:15   #4
M344587487
 
M344587487's Avatar
 
"Composite as Heck"
Oct 2017

31716 Posts
Default

P95 might be more optimised for intel than AMD because they've been the dominant examples of x86 for the majority of recent memory, but P95 is really optimised for x86 in general. There was an effort to implement the intel-only AVX512 and I think there were gains, but the downclocking and power usage that occurs when AVX512 is used made the results a little anti-climactic compared to what you might expect. There are differences like certain instructions taking a different number of cycles to complete on different architectures, but there are wide differences even within intel's numerous architectures so I don't think even P95 optimises fully down to a per-cycle basis.

Any Ryzen from Zen 2 onwards has full AVX2 support and oodles of cache so it's a good choice for P95. This post and the thread it's from has data on throughput vs intel ( https://www.mersenneforum.org/showpo...3&postcount=61 ). In the end intel and AMD both hit a memory bandwidth bottleneck, but AFAIK the cache makes AMD a throughput winner as for a given amount of work less bandwidth is required (I know nothing about the latest intel chips, they've made alterations to cache I'm not up to speed on). You may not be interested in gaming but the gamers favourite the 3600 is probably the best Zen 2 chip from a price-to-performance viewpoint, but it depends on the rest of the system.

The CPUs coming out this year based on Zen 3 should be interesting (Ryzen 4000), there's the usual generational IPC and clock gain benefits but they are also unifying the L3 cache so you have 32MiB shared per chiplet instead of the current Zen 2 which has 16MiB shared per quad core. This means that the cache can be more effectively utilised on the same workload and may provide quite a performance boost over Zen 2, worth watching at any rate.

But really if you're buying hardware specifically for PRP or P-1 you should get the Radeon VII, it kicks the crap out of anything else on a price-to-throughput, price-to-efficiency and price-to-density basis.

Last fiddled with by M344587487 on 2020-07-25 at 09:20 Reason: finish sentences
M344587487 is offline   Reply With Quote