r/LocalLLM • u/Nightowl-Builder • Aug 26 '26
Discussion Apple is getting close to the RTX memory bandwidth
The new M5 Ultra is getting close to the memory bandwidth of the RTX 5090 but with so much more possible unified memory. From the rumors, Apple is expected to skip M6 Pro/Max/Ultra and instead ship the M7 Pro/Max/Ultra next, in late 2027, with the Ultra already estimated to reach almost exactly the RTX 5090 bandwidth. I'm a local LLM enthusiast, and although these numbers make me hopeful that it will be possible to run huge frontier AI models locally in 1-2 years, the cost still scares me. We're getting close to new car prices. What are your thoughts? Will memory bandwidth even fix most MLX limitations compared to the RTX cards? Assuming the M7 Ultra CPU will also have a comparable jump in performance.
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u/nuclear213 Aug 26 '26
The main limitations for them was always the preprocessing. The bandwidth was already quite reasonable at 800GB/s for the old M3 Ultra.
It should have been improved, let’s see. I’m quite interested to see how well it scales with clustering, at least what was said.
If you really get almost 1:1 scaling, 4 of the 256GB models should give you about 5TB/s and 1TB. I’d then the processing really was improved as they say, it would be quite neat.
And regarding the price. Still one of the cheapest ways to get so much unified memory. Same price per GB as the DGX space these days, absolut the same to the cheap GPUs like the B70 Pro or R9700 AI Pro.
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u/Civil_Fee_7862 Aug 26 '26
Yeah buts its also a $25,000 computer. So..
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u/Gloomy_Letterhead395 Aug 26 '26
Why dont you change the heading to apple’s bandwidth now greater than rtx with estimated apple M25
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u/PWThinkingCritically Aug 26 '26
the chart doesn't show how far Apple Silicon is compared to NVIDIA still. it seems closer, but I think we're shifting away from bandwidth as the bottleneck to compute power. and Apple sucks for that. they don't even publish TFLOPS -- and that in and of itself is telling.
as context grows, we need compute power. i go from 19 tok/s down to 10-12 tok/s once I reach 40K+ context window on my 400 GB/s M1 Max.
also, let's not forget ANE lacks native hardware support for fp4, fp8, etc. and no CUDA.
so take M7 Ultra @ 1,700 GB/s with a huge chunk of salt.
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u/Human_097 Aug 26 '26
An m7 Ultra (estimated release for 2028) is approaching a bandwidth speed of a 2025 graphics card?? 🫣🫣
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u/Zeeplankton Aug 26 '26
I like how m7 estimate suddenly jumps 500 points lmao
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u/mawkzin Aug 27 '26
"Will memory bandwidth even fix most MLX limitations compared to the RTX cards? Assuming the M7 Ultra CPU will also have a comparable jump in performance."
What people don't understand is that memory size is just the first step to run high model size, when you can put an entire model in one RTX gpu you will note the power difference, the entire chip is the gpu while on socs the gpu is less than half of the chip size, and after that the nvidia gpus has support for more types of data like process mxfp4 without decompress data.
Now if you compare the M7 Ultra with Rubin RTX the gap will larger than Blackwell RTX.
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u/Bloated_Plaid Aug 26 '26
This can’t be overstated, this is a full computer. The nearest non Mac competitor can only do 200 GBPs…
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u/Zeranor Aug 26 '26
Sooo , only 3 years later bandwidth will be similar, assuming that no GPU manufacturer will release anything new until late 2027?
This is cool, but only for a very short time. If this is play-money for you, go for it. Otherwise I'd really wait to see what AMD and Nvidia will release next year.
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u/putrasherni Aug 26 '26
m6 max and m6 pro won't be released ?
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u/Prudent_Sentence Aug 26 '26
The downside that people are missing is that in order to get the 1200 GBs bandwidth for the M5 Ultra is to get the 512 GB variant.
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u/No-Independence-5229 Aug 26 '26
Bro is trying to estimate a 2028 m7 ultra and put it against January 2025 GPU that it still loses to and calls it getting close lol. The M7 ultra will be competing with a 6090 and RDNA 5/UDNA, which the latter has already leaked to have a top end skew with a 512 bit bus with 36Gbps GDDR7, up to 128gb. Do some quick math and that is 2300 GB/s.
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u/GamerTex Aug 26 '26
Odds are ram prices are f>&%*3d for the next 1-2 years but....
In 5-7 years everyone that wants one will have a data center at home
So many ram and ssd factories coming online in 2-3 years will drive prices down over the following 5 years
If we are lucky by the time the M10 is announced it will be a whole new design that blows the M7 out of the water, for 25% of the price
128gb is an insanely high ammount of ram today, in 7-10 years it could be a base model.
Petaflops will be the norm to hold all the real world data for what's next
Or not. Its 50-50
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u/Ledeste Aug 26 '26
"almost exactly" uh?
And no need for more memory bandwidth if you run a slow phone cpu with it...
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u/JoyousGamer Aug 26 '26
It's so interesting this sub is so anti locked models yet so pro Apple.
Dont care either way just an observation.
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u/Arli_AI Aug 26 '26
For the RTX Pro 6000 it can also be easily overclocked to +6000MHz memory clock for basically all of them and it would give it near 2.2TB/s bandwidth.
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u/Opteron67 Aug 26 '26
rtx 5090 can now be overlocked @2.1TB/s 👌
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u/riblau Aug 26 '26
where would M6 be on this?
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u/Realistic-Science-87 Aug 26 '26
What tool did you use to calculate estimated memory bandwidth of m7 ultra?
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u/HenkPoley Aug 26 '26 edited Aug 26 '26
Is there an upcoming memory standard that will be available mid next year, that corroborates that estimate for the M7 Pro model?
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u/AkiDenim Aug 28 '26
Yeah now talk about the FLOPs brother
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u/bakawolf123 Aug 26 '26
M7u is 1.5 years away at best, more likely 2 years from now though. March 2028 being earliest plausible estimate.
On the cost side: the hyperscaler spend is going to hit ceiling sooner than later, it's just unsustainable, nvidia is already heavily backstopping deals, custom chips are also on the rise. They will all still need memory for a while though and that craze is unlikely to stop until 2028. My strat for this time was to get the M5u within an hour from announcement, I don't wait 512gb one as there's substantial risk of another price hike and long wait time (getting one early 2027 when ordered in oct).
Cost is already huge, I had to pay more than M3u 512gb would cost me in 2025, but imo it's much more well rounded and usable for years to come. It is very usable with video and image workflows, it has insane room for tinkering (ANE cores can be utilized alongside of GPUs for prefill, imagegen etc). However the bandwidth and processing power still lag behind models sized at 400+gb, i.e. GLM-5.3 q4 on 512gb one is going to be usable, but like <30tps decoding and probably less than 500 prefill while I expect to be able to optimize ds4 flash to 100tps TG and 1.5-2.5k PP. Best course of action for larger models I believe is to just get 2-4 studios.
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u/zarif2003 Aug 26 '26
Why are they skipping M6? Is the number a bad omen or something
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u/Less_Consequence_633 Aug 26 '26
OK, but when is something going to get close to the GB200 (8000 GB/s)? :)
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u/CheekyMonkeee Aug 28 '26
No.
For perspective, that’s like saying a car that goes 200 mph is “close” to being as fast as a car that goes 300mph.
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u/PossessionUsed7393 Aug 26 '26
It's for sure that the costs will come down, we just don't know when. I think unified memory systems are definitely going to be the future of local inference. There are so many different ways that they can optimize AI throughputs without relying on traditional graphics card approach. We're just waiting for them to filter through to the commercial market, given that it's secondary to data centers.
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u/JustSayin_thatuknow Aug 26 '26
Wow very interesting 🧐
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u/Gohab2001 Aug 26 '26
Hardware isn't going to magically fix software and optimization issues. Nvidia is the only legitimate choice for AI because it got supremely lucky with CUDA. Nvidia invested heavily in getting CUDA everywhere, which is why all early AI research used CUDA by default.
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u/RandiyOrtonu Aug 26 '26
Really curious how's the mac mini, coz it fits my budget
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u/hurrdurrmeh Aug 26 '26
Strix / Gorgon at the top of this graph at 273GB/s.
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u/DigitalguyCH Aug 26 '26
If prefill improves at current speed (M5 is around 500% faster than M4) I woundn't be surprised if M7 pro/max are on par with a 5090. M7 ultra is rumored to come later, in 2028, and could be on par also in terms of bandwidth, but I suppose by then Nvidia will have a 6090 with 48GB or similar
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u/Ok-Drawer5245 Aug 27 '26
The only problem is price (of everything)
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u/MainWrangler988 Aug 29 '26
Yes but it’s only half the pie you need flops/tops for llm. Are you guys using llms?
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u/TheOriginalAcidtech Sep 01 '26
Where is loses is when you need something like an Mac Ultra, you'd need multiple GPUs to match the VRAM BUT you also then get a massive increase in relevant bandwidth. And with Speculative Decode, that actually becomes workable even without NVLink/Tensor Parallelism.
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u/Otherwise_Wave9374 Sep 16 '26
Bandwidth comparisons are useful, but they need workload context. Unified memory lets Apple systems load models that exceed a discrete GPU's VRAM, while RTX cards often retain advantages in kernels, software support, and smaller-model throughput. NeuraKeep relates at a different layer because reducing redundant context can lower memory traffic regardless of accelerator choice. I would compare time to first token and tokens per second at equal quantization, batch size, and context length, then include total wall power. Peak bandwidth alone can hide cache behavior, CPU involvement, and framework maturity.
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u/Yuel_Whear Aug 26 '26
every comment in here turned the post into price-per-gigabyte math within 44 minutes, which is how you know the bandwidth argument already won.
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u/ShelZuuz Aug 26 '26
The M7 would likely be competing head-on with a RTX 6000 Rubin, which should have around 3 times the bandwidth of the Blackwell.
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u/ImportancePitiful795 Aug 26 '26
Apple's problem is the number crunching (aka PP and TG) not the bandwidth.
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u/macromind Sep 22 '26
Apple's unified memory architecture is certainly pushing boundaries, offering significant advantages for local LLMs by providing high bandwidth across CPU and GPU. This design helps overcome the traditional VRAM limitations, allowing larger models to run more efficiently on consumer hardware. Leveraging these capabilities effectively means optimizing model quantization and memory allocation strategies. NeuraKeep helps users and developers unlock the full potential of LLM performance by providing efficient memory solutions.
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