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Arm's Cortex X925: Reaching Desktop Performance

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111–120 of 169 posts

Re: Arm's Cortex X925: Reaching Desktop Performance

#111
post #2

Kind of weird to see an article about high-performance ARM cores without a single reference to Apple or how this hardware compares to M4 or M5 cores.

They are talking specifically about ARM cores designed by and licensable from ARM Holdings (the company), not other designs that don't use ARM's designs (like the Apple silicon).

Re: Arm's Cortex X925: Reaching Desktop Performance

#112

Earlier quoted context omitted.

The core they're talking about was released about two years ago. nvidia stuck it on their grace blackwell (e.g. DGX Spark) as basically a coordinator on the system. Anyway, here it is in GB10 form- https://browser.geekbench.com/v6/cpu/14078585 And here is a comparable M5 in a laptop- https://browser.geekbench.com/macs/macbook-pro-14-inch-2025 M5 has about a 32% per core advantage, though the DGX obviously has a much…

Afaict the "desktop" target is meaningless these days. Desktops aren't really a thing anymore in the general sense are they? Only folks I know still hanging on to desktop hardware are gamers and even those I see going by the wayside with external video cards becoming more reliable. "Daily driver" is probably a better term, but everyone's daily usage patterns will vary. I could do my day job with a VT100 emulator on a…

There's a zillion office workers that have low cost mini PCs from the big OEMs on their desk. After all, all those off-lease mini PCs on eBay that are so beloved by home lab enthusiasts have to come from somewhere.

Re: Arm's Cortex X925: Reaching Desktop Performance

#113
post #15

I can't seem to find any power draw or efficiency figures (e.g. /watts). Only found this which talks about performance-per-area (PPA) and performance-per-clock ()I assume cycle) (PPC): https://www.reddit.com/r/hardware/comments/1gvo28c/latest_ar...

We should have N1X vs. X2 vs. M5 laptop battery life reviews in a few months.

Re: Arm's Cortex X925: Reaching Desktop Performance

#114
post #14
post #10

Earlier quoted context omitted.

That would only matter (to me, at least) if those Apple chips were propping up an open platform that suits my needs. As things stand today, procuring an M chip represents a commitment to the Apple software ecosystem, which Apple made abundantly clear doesn't optimize for user needs. Those marginally faster CPU cycles happen on a time scale that anyway can't offset the wasted time fighting MacOS and re-building decade…

Sure. Insofar as Apple Silicon beats these things, "I'll take less powerful hardware if it means I'm not stuck with the Apple ecosystem" is a perfectly reasonable tradeoff to make. Two things, though. First, I don't like making blind tradeoffs. If what I need (for whatever reason) is a really beefy ARM CPU, I'd like to know what the "Apple-less tax" costs me (if anything!) Second, the status quo is that Apple Silicon…

Are M* chips even beating AMD anyway?

Re: Arm's Cortex X925: Reaching Desktop Performance

#115

Why would I care about desktop performance without the PC desktop ecosystem where everything 'just works'? Universal ARM linux distros aren't supported by anything.

Why would you not be able to build a PC around it? That's what you do with PowerPC.

Re: Arm's Cortex X925: Reaching Desktop Performance

#116

Earlier quoted context omitted.

This the the most cursed part of modern cpu design, but the TLDR is that programs use virtual addresses while CPUs use physical addresses which means that CPU caches need to include the translation from virtual to physical adress. The problem is that for L1 cache, the latency requirement of 3-4 cycles is too strict to first do a TLB lookup and then an L1 cache lookup, so the L1 can only be keyed on the bits of ram wh…

Can you not take some of those virtual bits and get more buckets that way? I am sure it will make things more complicated if nothing else by them possibly being mapped to the same physical page, but it doesn't sound like an impossible barrier. Maybe something terrible where a cache line keeps bouncing between different buckets in the rare case that does happen, but as long as you can keep the common case as fast... O…

that will break if any page is mapped at two VAs, you'll end up with conflicting cache lines for the same page...

Re: Arm's Cortex X925: Reaching Desktop Performance

#118
post #2

Kind of weird to see an article about high-performance ARM cores without a single reference to Apple or how this hardware compares to M4 or M5 cores.

They are talking specifically about ARM cores designed by and licensable from ARM Holdings (the company), not other designs that don't use ARM's designs (like the Apple silicon).

They repeatedly compare to Intel and AMD cores though, which are x86. If they’re worth a mention, then so are some of the other ARM consumer desktop chips on the market regardless of who designed them. Apple was one of the closest ARM chips they could have compared to.

Your “specifically ARM cores designed by and licensable from ARM Holdings” argument doesn’t hold any water.

Re: Arm's Cortex X925: Reaching Desktop Performance

#119
post #26

But with hardware IP locks like x86_64. Better favor as much as possible RISC-V implementations. But, I don't know if there are already good modern-desktop-grade RISC-V implementations (in the US, Sifive is moving fast as far as I know)... and the hard part: accessing the latest and greatest silicon process of TMSC, aka ~5GHz. Those markets are completely saturated, namely at best, it will be very slow unless somethi…

> Sifive is moving fast as far as I know)

worked with their cores in $pastJob. I'd say their main products are flowery promises and long errata sheets.

Re: Arm's Cortex X925: Reaching Desktop Performance

#120
post #14

Earlier quoted context omitted.

Sure. Insofar as Apple Silicon beats these things, "I'll take less powerful hardware if it means I'm not stuck with the Apple ecosystem" is a perfectly reasonable tradeoff to make. Two things, though. First, I don't like making blind tradeoffs. If what I need (for whatever reason) is a really beefy ARM CPU, I'd like to know what the "Apple-less tax" costs me (if anything!) Second, the status quo is that Apple Silicon…

Are M* chips even beating AMD anyway?

On average according to Geekbench, the M5 compared to the 9950X is ~17% faster in single thread performance and ~30% slower in multithread performance.

Individual benchmarks tell the bigger picture. These two are optimized for different use cases, with Apple heavily leaning towards low latency single thread throughput with low sustained power usage.

https://browser.geekbench.com/v6/cpu/compare/16833358?baseli...

EDIT: The M4 Max compares much more closely https://browser.geekbench.com/v6/cpu/compare/16834801?baseli...

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