Last updated: July 2026
Key Takeaways
- The M5 Ultra Mac Studio is reportedly targeted for late 2026, but the date depends on the DRAM market, not Apple's calendar, and the tested 768GB memory ceiling is not a shipping promise.
- Waiting is currently the only Apple path to a high-memory Studio: the M3 Ultra has been quietly cut to a single 96GB configuration, with the 256GB and 512GB options pulled from sale during 2026.
- Most local AI workloads never needed an Ultra. If your models fit in 24 to 128GB, cheaper hardware you can buy today is the honest answer, and the decision tree below maps it.
The usual question about an upcoming Mac is when Apple will ship it. The question hanging over the M5 Ultra Mac Studio is different: when will the memory market let Apple ship it. The refresh has reportedly slipped from a mid-2026 target toward October, the current model has been quietly stripped of its high-memory configurations, and the one genuinely exciting rumor, support for up to 768GB of unified memory, collides directly with the worst DRAM shortage in decades.
That makes the buy-or-wait math unusual this cycle. Both choices run through the same constrained supply chain, and for anyone whose real goal is running large AI models locally, the honest analysis says something most coverage skips: you may not need this machine at all. Here is what is actually known, what 768GB would and would not run, and how to decide.
What We Actually Know About the M5 Ultra Mac Studio
Everything below is reporting, not a spec sheet. Per Bloomberg's Mark Gurman, summarized by MacRumors in late June, Apple has two Mac Studio refreshes in the pipeline: an M5 Ultra model due in 2026 and a more significant M7 Ultra model in 2028. The Studio's Ultra tier skips a generation on each side of the M5: no M4 Ultra ever shipped, since the M4 Max lacks the UltraFusion interconnect that fuses two Max dies into an Ultra, and no M6 Ultra is planned.
The M5 Ultra itself is expected to be an incremental core-count step, roughly 36 CPU cores and 80 GPU cores against the M3 Ultra's 32 and 80. The chassis stays the same; per AppleInsider's read of the same newsletter, the notable internal change is an upgraded heatsink aimed at sustained AI workloads. The headline is memory: Apple has reportedly tested configurations up to 768GB of unified memory, which would be the largest single-box memory pool ever offered in a consumer-adjacent machine.
Timing is the soft spot. Gurman's April reporting pointed to roughly October after the original first-half target slipped, and his June reporting kept 2026 without recommitting to the month. Current M3 Ultra orders already show delivery estimates stretching months out, which does not suggest a supply chain with slack in it. Treat October as the working assumption and the 768GB ceiling as tested, not promised.
Why It Is Late: The Memory Shortage Is Writing Apple's Roadmap
The delay is not a chip problem. It is a memory problem, and it is the same one raising prices on everything with DRAM in it. AI datacenters are on track to consume roughly 70 percent of the world's memory output in 2026, a squeeze we broke down in our memory shortage analysis and our guide to when RAM prices will come down.
Watch what the shortage has already done to the current Mac Studio, because it previews what could happen to the next one. In early March 2026, the 512GB M3 Ultra configuration disappeared from Apple's store without announcement, and the 96GB-to-256GB memory upgrade rose 400 dollars to 2,000 dollars, as Tom's Hardware reported at the time. By early May, the 256GB option was gone too. The M3 Ultra, launched with Apple boasting it could hold 600-billion-parameter models entirely in memory, now sells in exactly one memory configuration: 96GB. The Mac mini lost its 64GB and 32GB tiers in the same wave, and Gurman reports Apple is prioritizing its notebook lines for the memory it can get.
The detail that should recalibrate expectations: Tom's Hardware notes Apple had long-term DRAM supply agreements running through early 2026, better positioning than most PC vendors, and the high-density tiers vanished anyway. If ultra-high-capacity memory is scarce for a buyer of Apple's size, a 768GB launch configuration in October is a hope, not a plan. The company that famously controls its entire stack is discovering the one layer it does not control, and that layer is currently deciding its product calendar.
What 768GB of Unified Memory Would Actually Run
Here is the analysis the rumor coverage skips: mapping the tested ceiling against the open-weight models people actually want to run. The rule of local inference has not changed. The model's weights must fit entirely in memory, VRAM plus RAM on a PC or the unified pool on a Mac, or generation speed collapses. The figures below are Q4-quantization weight floors drawn from our local AI models by VRAM guide.
| Model class | Memory floor (Q4 weights) | Fits in 768GB? | Fits in today's 96GB M3 Ultra? |
|---|---|---|---|
| 70B-class dense (Llama tier) | 35 to 40GB | Yes, with room for several at once | Yes |
| Step 3.7 Flash, 198B sparse MoE | 110 to 120GB | Yes, comfortably | No |
| Frontier-adjacent 280B-class MoE | Roughly 130GB and up | Yes | No |
| Kimi K2.7-class, smallest published quant | About 340GB, needing 350GB-plus total | Yes, moving it from server-class to one box | No |
| Kimi K3, 2.8T parameters | Realistic floor near 1TB | No | No |
Weights-only floors at roughly 4-bit quantization. The operating system, inference runtime, and context window add overhead on top. The 768GB figure is a tested ceiling from supply-chain reporting, not a confirmed shipping configuration.
Read the table honestly and two findings stand out. First, 768GB would be genuinely transformative in the middle: it moves the 340GB-class open agents like Kimi K2.7 from multi-GPU server territory into a single quiet box, which is exactly the machine local-AI builders have been asking for. Second, it still does not reach the very top. As we found in our Kimi K3 hardware reality check, the largest open model's realistic floor sits near a terabyte. Even the most optimistic rumor about Apple's next flagship does not put the biggest open weights in one box. The frontier is outrunning the hardware, shortage or no shortage.
The Buy-or-Wait Decision Tree
If you need maximum unified memory now
The uncomfortable truth: Apple currently sells you nothing. With the M3 Ultra capped at 96GB, there is no high-memory Mac Studio to buy new, which quietly settles the wait-or-buy question for this group. Your real options are the used and refurbished market for 256GB and 512GB M3 Ultra units, which have understandably held their value, a non-Apple unified-memory machine such as AMD's Ryzen AI Max 395 platforms with 128GB, or waiting for October and accepting the risk that launch configurations arrive constrained or repriced. Macworld's testing adds one more wrinkle worth knowing: the M5 Max chip already beats the M3 Ultra on CPU performance, so a used M3 Ultra is a capacity purchase, not a speed purchase.
If your models fit in 24 to 128GB
This is most readers, and the honest answer is that you never needed an Ultra. The best models per gigabyte live in this range, as our local AI hardware guide lays out in detail. A Mac Mini M4 handles the 12B-to-30B class that covers everyday assistant and coding work, and a used RTX 3090 remains the best dollar-per-VRAM value in 2026 for GPU inference, holding 24GB models with room for long context. Neither purchase gets better by waiting for a machine you will not fully use, and both dodge the launch-window pricing that the shortage makes likely.
Check Price on Amazon: Apple Mac Mini M4
Check Price on Amazon: NVIDIA RTX 3090 24GB (Renewed)
If only the M5 Ultra will do
Then wait, but wait with a plan. Assume the top memory tiers will be supply-limited at launch, because the current lineup's history says exactly that, and be ready to order early rather than deliberating through a sold-out window. Budget for the possibility that the shortage prices the highest configurations above what the M3 Ultra equivalents cost, and treat the 768GB tier as a bonus if it ships rather than the reason you waited. If October slips, the used M3 Ultra market is your bridge, not the 96GB new unit.
The Part Apple Cannot Control
Apple designs its own silicon, writes its own operating system, and runs its own stores, the most vertically integrated stack in consumer computing. And in 2026 its flagship desktop is delayed, de-configured, and repriced by the three companies that make roughly 90 percent of the world's DRAM. Whoever controls the infrastructure controls the experience, and this year the infrastructure is memory. That lesson applies at every scale, including yours: hardware you own outlasts product cycles you do not control, which is why the machines in our guides are chosen for what they run today, not for what a supply chain might permit in October.
Frequently Asked Questions
When will the M5 Ultra Mac Studio be released?
Reporting from Bloomberg's Mark Gurman points to late 2026, with October as the working target after the original mid-2026 window slipped due to memory supply constraints. Apple has confirmed nothing, and the date remains dependent on DRAM availability rather than product readiness.
Will the M5 Ultra Mac Studio really have 768GB of RAM?
Apple has reportedly tested configurations up to 768GB of unified memory, but a tested ceiling is not a shipping promise. Given that the shortage forced Apple to pull the current model's 256GB and 512GB options entirely, a constrained or delayed rollout of the top tiers is the realistic expectation.
Is the M3 Ultra Mac Studio still worth buying now?
New, only in narrow cases: it sells in a single 96GB configuration, and the M5 Max already outperforms its CPU. For high-memory needs, the used and refurbished market for 256GB and 512GB units is currently the only Apple-silicon path, and those machines remain excellent capacity buys.
Could the M5 Ultra run the largest open models like Kimi K3?
Not even at the rumored ceiling. Kimi K3's realistic memory floor sits near 1TB, above a 768GB pool. It would, however, comfortably run everything below that, including 340GB-class models such as Kimi K2.7 that currently require multi-GPU server hardware.
Why did Apple skip the M4 Ultra and M6 Ultra?
The M4 Max shipped without the UltraFusion interconnect needed to fuse two Max dies into an Ultra, so no M4 Ultra was possible. On the roadmap side, Gurman reports Apple plans to jump from the M5 Ultra directly to an M7 Ultra in 2028, concentrating its high-end silicon work on that generation.
What is the best local AI hardware while waiting?
Match the machine to your model sizes. A Mac Mini M4 or a modern mini PC covers the 12B-to-30B class, a used RTX 3090 is the value pick for 24GB GPU inference, and 128GB unified-memory machines handle the 110GB-class sparse models. Our local AI hardware guide and VRAM-tier guide map the full range.
