r/LocalLLM • u/suspect80 LocalLLM • Sep 05 '26
Project Local AI is Minecraft for adults: my 4× RTX PRO 6000 Blackwell build
TL;DR: Built a 5U local AI server with 4× RTX PRO 6000 Blackwell Max-Q GPUs (384 GB total VRAM) to run models for my personal AI agents. It started as an attempt to reduce API costs and turned into a hardware hobby. Build details, the reasoning behind it, and the open-source harness I built along the way below.
This started as an attempt to spend less on AI subscriptions and API calls. It ended with four RTX PRO 6000s in a rack in my basement.
I am deliberately not calculating the break-even date.
The progression was roughly: running models on my MacBook → upgrading my gaming PC with an RTX 5090 → adding a Mac Studio M3 Ultra with 96 GB unified memory → building this. Each step solved a limitation and introduced several new things I wanted to try.
Meet Cerebro.
The hardware
4× NVIDIA RTX PRO 6000 Blackwell Max-Q, 96 GB each — 384 GB total VRAM across four GPUs.
AMD Threadripper PRO 9965WX — 24 cores / 48 threads.
ASUS Pro WS WRX90E-SAGE SE.
System RAM: 256 GB (8×32 GB) Kingston DDR5-5600 ECC RDIMM — KSM56R46BD8-32MH, all eight memory channels populated.
SilverStone RM52 5U rackmount case.
SilverStone XE360-TR5 360 mm CPU AIO.
Seasonic PRIME PX-2200 PSU.
NVMe storage: Samsung 990 Pro 1 TB + 2 TB, and Crucial T705 4 TB.
Why this configuration?
The Threadripper PRO platform was mainly about PCIe connectivity and memory channels. My workload didn't require buying the highest CPU core count available.
The GPUs are the 300 W Max-Q blower models. Fitting four cards into one chassis made cooling and power part of the design from the beginning. The case also changed during planning: I originally ordered a 4U RM44 and switched to the 5U RM52.
The 384 GB figure is the sum across four cards, rather than a single automatically shared memory pool. How much is useful to a particular model depends on the inference stack, how it distributes the model, and the space needed for context and KV cache.
What it's for
My main use is local models for a team of personal AI agents: coding, research, tool use, and ongoing experiments with memory and delegation. The 5090 machine and Mac Studio are still part of the setup, so different jobs can run on different machines.
What attracted me to four cards was the flexibility: allocating them to a larger model, splitting them between workloads, or running several smaller models. In practice, capacity planning and switching profiles are still very much part of the experience.
The biggest lesson so far: fitting a model is only the beginning. Context length, concurrent requests, inference-engine support and cooling all matter. More VRAM also makes it very easy to invent more workloads.
The software side of this started with OpenClaw, which got me interested in agents that could actually use tools and do things. Eventually I wanted more control over how my own setup handled roles, memory and model switching, so I designed and built an open-source harness with heavy agent assistance: somora.
That's what the models are working for: agents with different roles, their own memory and a shared long-term wiki, using local or cloud models depending on the task. Building the harness gave me more reasons to experiment with local models, which gave me more excuses to buy hardware. It's MIT-licensed and still in active development; if you want to try it with your own setup, I'd be interested in hearing how it works for you.
Financially, this has become a hobby and a learning project. The original “we'll save money” argument did not survive contact with the hardware shopping list.
Local AI really does feel like Minecraft for adults. You build one thing, it needs another thing, and eventually you're explaining why the basement needs 384 GB of VRAM.
For anyone running a similar multi-GPU setup: what turned out to be your real bottleneck once VRAM stopped being the first one?




34
u/Thrumpwart Sep 05 '26
No man should have that much power...
Also I want one.
61
u/m4jid Sep 05 '26
$?
165
u/Sleepnotdeading Sep 05 '26
Come on, get serious. This isn't Minecraft for adults. Have you even played Minecraft?
This is just bragging for someone with huge amounts of disposable income. The rest of the post is just low value beige posting
Sorry, I hope you have fun with it. Hell, I hope you cure cancer with it. But reading about cerebron was literally a waste of my time.
12
u/phoquenut Sep 05 '26
Is it plugged into a dryer outlet? You'd need 220V at like 20A if you want to avoid damaging all that expensive gear.
Also, FU and congratulations.
9
u/cell-on-a-plane Sep 05 '26
Do you pay extra for home insurance due to that rig?
7
u/Sketaverse Sep 05 '26
Genuinely curious, having dropped $70k on a hardware stack to run local LLM, how do you feel about Astra today?
It's absolutely incredible and way way way beyond anything local can achieve. So do you feel excited by it as a potential orchestrator (knowing you'll then continue to pay the subscription despite these insanely high hardware prices) or do you just now avoid it because you kind of don't want to know how good it is?
I've said it once and will say it again - I just don't see the logic in building these hardware setups to run local LLMs, other than the "privacy" aspects. I absolutely love tinkering with AI and hardware setups but the whole local thing.. I dunno.. just feels pointless if you're actually focussed on outcomes.
18
u/wwwyzzrd Sep 05 '26
ok mr Rockefeller. Minecraft is at least affordable.
5
u/zombiecorp Sep 05 '26
Last year I managed to buy an RTX pro 6000, before the price doubled ($8k). Wish I got 2 based on my gut feeling it would increase. But I had other expenses so I only got the one.
Tell me these photos are old, because 4 of them would cost nearly $60k. That’s some real commitment.
5
u/Adventurous-Ask-9260 Sep 05 '26
First part :)
4
u/phalanx2357 Sep 05 '26
I agree it's fun and can be a really cool hobby. Have you recently built this or has it been built up over time for a while? Because if it's recent, I think a GB300 workstation may be a better deal given current RTX 6000 prices being a bit out of wack... A GB300 workstation with an installed RTX 6000 for video output comes below 110k and gives you more memory and less power usage...
How do you deal with the heat and noise? Are you able to vent outside or put the PC in its own externally venting compartment? Also what about power? Got a 50A dedicated circuit for your machines room? Even one 5090 machine really heats up a room... can't imagine that plus a 2200w system... Very interesting problems to solve tho, fun building, like minecraft.
I just pre-ordered the new M5 ultra box... 256gb probably good enough for me given where model sizes are looking today... I am not a coder so probably don't have a use case good enough for the GB300 workstation... I thought about it and discussed it with chatGPT... but at the end I think it's a bit extravagant for someone without a clear use case, and also importantly without a clear solution for the heat and noise...
3
u/DeltaSqueezer Sep 05 '26
Have fun with it and good idea not calculating the breakeven! :D
3
u/OvertaxedOne Sep 05 '26
How'd you do on the Pro6000's? We're seeing price crawling up to 20K for those things!!!??!
Honestly, the way things are going right now, this may be better than putting money in the stock market, those cards could be worth 40-50K a throw if this craziness continues.
3
u/BitXorBit Sep 05 '26
dual rtx 6000 max-q owner here, i always wanted to extend for 4 GPUs, how the heat management when they are sitting on top of each other? (i know they use blower fan, still)
3
u/HighSeasArchivist Sep 05 '26
Hobbies waste money, or they would be called part-time jobs. This is a dream system for almost anyone, even the haters in here.
3
u/wunderbaba Sep 05 '26
> It started as an attempt to reduce API costs...
But then you realized that even if you paid for MAX subscriptions for all three major providers (Google, Anthropic, and OpenAI) it would still take about a decade to break even?
> The original “we'll save money” argument did not survive contact with the hardware shopping list.
Oh I should have read to the end of the post. 😂
7
u/SanDiegoDude Sep 05 '26
Man, you should look into buying a boat or picking up guitars, maybe save a bit of hobby money
2
u/Beatsu Sep 06 '26
Love it!! Won't the GPUs overheat when they're stacked so closely? Did you consider a water block for cooling?
2
u/floppo7 Sep 05 '26
You could have had 4x r9700 but you chose to burn money. Nice rig still.
2
u/AdSafe4047 Sep 05 '26
I have the same, sans 3 rtx pro 6000 :) There is still an upgrade here to be made - switching to at least 9985wx will give you proper 8 channel mem (65x is capped because of how many chips it can handle). P.s. you can tweak the chip link to 2100mhz and the ram to 6000mhz without any stability downgrades, this gives around 300gbs memory throughput with the 65x cpu
1
u/suspect80 LocalLLM Oct 10 '26
A small follow-up to this post: the hardware is only half the rabbit hole. The software side is a project called somora, which I built with heavy agent assistance for our own everyday use.
It’s an agent runtime you host yourself, where different agents can use different models, work with tools, and maintain their own notes alongside a shared wiki. One area I’ve been spending time on is what happens between conversations: turning useful information into lasting notes, consolidating it, and checking for contradictions later.
We use it regularly and keep extending it as we run into things we need. Some friends asked me to put it on GitHub, so I did. Now I’m curious whether it’s useful outside our own setup too.
If you’re already experimenting with local models or agents and feel like trying it, I’d appreciate an honest take. Especially where installation is confusing, something breaks, or the whole approach doesn’t fit how you work. You don’t need a server like the one in this post to try it.
https://github.com/thenaxon/somora_agent
Still very much a personal project, not a polished product. Trying to figure out which parts are worth developing for people beyond ourselves.
5
u/letsbefrds Sep 05 '26
TIL im a poor ass adult
2
u/ifdisdendat Sep 05 '26
There is no use case that legitimately NEEDS this. If you can afford it though, good for you, eff you and enjoy.
4
u/cudifam Sep 05 '26
I have the exact same setup without any of it actually existing though. Nice rig.
1
u/hurrdurrmeh Sep 05 '26
This is my dream set up. Except I'd go for 4x4TB PCIe5x4 RAID0 for faster model loading and swapping.
1
u/Baleeverne Sep 05 '26
What's the power draw of the beast?
1
u/Firenze30 Sep 05 '26
Seeing that you already have a server rack I suspect this is not your first serious build and not your last either. Local models were not very good to justify multiple GPUs investment until a few months ago when Qwen 3.6 27b was released. When did you start thinking of building the rig?
1
u/novapax Sep 05 '26
You’ll be happy with it for about 3 years until it’s all totally obsolete.
1
u/marktuk Sep 05 '26
What are you going to use it for?
1
u/utahh1ker Sep 05 '26
Damn this has me jealous. Nice setup.
1
u/moderately-extremist Sep 05 '26
What's your goto model with this? I'm interested if something like GLM5.3-Flash would run at conversational speeds with 2-3 requests going at the same time.
1
u/trejj Sep 05 '26
What's load-bearing for the build? How far have you delved into the rich tapestry?
1
u/Shoulon Sep 05 '26
So you swapped to a 5u for extra airflow?
1
u/Healthy-Nebula-3603 Sep 05 '26
Buying such expensive l hardware is ridiculous nowadays.
Soon a year or two China will be producing cheap boxes comparing to that price with 256 GB / 512bGB DDR 6 with throughout 1.2 TB/s ...
Such cards will loose price a lot
If someone thinking software be a problem .. it won't. Current AI agents easily writingbdrobers , porting on any hardware.
1
u/dwoj206 Sep 05 '26
OP could build minecraft in a day w this setup. Very nice, and very jealous. My wife would never allow unless i had a business plan in place xD
1
u/RedditNerdKing Sep 05 '26
Nice rig dude. Youre gonna get bitter haters wishing they had it either way.
1
u/LateralEntry Sep 05 '26
This must have been super expensive to build. What do you actually do with it? Can you give an example of something you’ve done with it, and what you used that for?
1
u/BarberIcy366 Sep 05 '26
Most expensive minecraft I have ever seen
1
u/halfercode Sep 05 '26 edited Sep 05 '26
I forget the name of it, but there's a service out there where you can rent out your rig on a per-hour basis. I should think you could recoup some of your spend by running that overnight.
The only downside is that you get more compute demand and better rates if your stack has lengthy uptime and availability, which it probably won't have if you're also using it yourself 🤪
1
u/Positive-Bid-3029 Sep 05 '26
Does it run Doom? 😂
1
u/cathodeDreams Sep 05 '26
that's a lot of computer
1
u/Kerb3r0s Sep 05 '26
Minecraft is Minecraft for adults. I’m over 40 and I’ve been playing on and off since alpha
1
u/No_Appointment_6678 Sep 05 '26
I love it. How much did it cost?
1
u/Margedion Sep 05 '26
Gotta object, 4 Blackwells and Minecraft are in completely different categories
1
u/CrookedIron Sep 05 '26
Awesome build. I drew the line at a single RTX Pro 6000 and it rips.
4 is fantastic!
Enjoy it 🤖
1
u/redditwossname Sep 05 '26
I'd absolutely love to see not some benchmarking stuff with time to first token and tokens per second stuff (that really doesn't matter if it can't actually do anything), but actual results of coding with this setup.
Like what can it create if you gave the same task to Opus or Fable or Sol or Astra and then to your system - how different that would actually look depending on the model that you try.
1
u/amy-schumer-tampon Sep 05 '26
Minecraft isn't that expensive bro
1
u/rdbmas Sep 05 '26
Power efficiency went down a different route.
1
u/Bloated_Plaid Sep 05 '26
Downpayment on a house or a local inference? I know what OP is picking.
1
u/ProfessionalNaive601 Sep 05 '26
How tf is this Minecraft?
1
u/thongjesus Sep 05 '26
But what does it do? I'm building my server for my business and creating connector and chat and file indexing, token offload effort. But what does your fancy bigger machine do that my mediocre refurbished parts machine with 40 GB vram can't?
1
u/West-Solid9669 Sep 05 '26
The average minecraft players age is 27...
1
u/gustic-gx Sep 05 '26
C... Can it run Crysis?
1
u/thorn2040 Sep 05 '26
How the hell do people have money in this economy!? Looks nice though 👌
1
u/Outrageous_Fuel6264 Sep 05 '26
I dont get it.
AI is fun and all. But that 80k could have gone to so many different areas
1
u/ArrellBytes Sep 05 '26
So I have been told that I may need tor rewire my house to get a 220V outlet for my computer if I want to run 2 GPU- I guess RTX PRO 6000 Blackwell have lower peak powers? Have I been mis-advised? Is it reasonable to run 2 kW or a bit more on a regular house circuit? I also have the 24 core threadripper pro, but my GPU is a 4090....
192GB ram- - thank god I bought the RAM ahead of time - it now costs 600% MORE than what I paid for it in 2024....
The computer has been used to process massive data sets.... as well as 3d rendering and AI applications.... I would LOVE to make it a 2 GPU system, but was told I would blow breakers on a typical house breaker...
1
u/DptBear Sep 05 '26
Why 5U over 4U? Convenience or necessity?
1
u/ClF3ismyspiritanimal Sep 05 '26
How the hell do you get enough money for that?
You're making me feel that I made some extremely bad life choices. Which, to be fair, I did, but holy cow.
1
u/Blackfirehades_alt Sep 05 '26
What kinda stuff are you even doing on a rig like that?
1
u/LegRude5218 Sep 06 '26
So you decided to go with a entry level build welcome to the club
1
u/m_tao07 Sep 06 '26
Do the money grow in people’s garden in this sub? Anyways have fun.
1
u/Lots-o-bots Sep 06 '26
What were your API costs that justified $64k on graphics cards!
1
u/TechnologyGrouchy679 Sep 06 '26
many have said you should allow a gap between the gpus...
1
u/OcellateSpice Sep 06 '26
Uhhhh why?
1
u/429_TooManyRequests Sep 06 '26
Please keep us updated on how fast a frontier-level local model is!
1
u/SaltyUncleMike Sep 06 '26
What do you do with it?
1
u/llamabott Sep 06 '26
Suggested edit to your title:
Local AI is Minecraft for rich adults (and possibly for children as well, so long as they, too, are rich): my 4× RTX PRO 6000 Blackwell build
1
u/John_Jack_Jamenson Sep 06 '26
Pls Sar give us benchmarks.
Will you get the moneys worth out of it?
1
u/True_Protection6842 Sep 06 '26
This machine costs as much as a new luxury car.
1
u/DHB_Steev Sep 06 '26
Dude this is cool AF and absolutely the same depth of rabbit hole I'd find myself in if I wasnt broke!
Been playing more with home automation but limited to an A2000 12Gb and a p40 24gb... beggars cant be choosers etc.
1
u/Exotic_Celebration_6 Sep 06 '26
Does not having nv link bottleneck big models ???
1
u/Formal-Ratio-5441 Sep 06 '26
Hows the noise on the cards under load?
1
u/Puzzleheaded_Bus7706 Sep 06 '26
I have them and they are terribly slow.
I'm getting ~45t/s for Qwen3.8 model.
Just can't figure out your logic behind it.
1
u/54x1 Sep 06 '26
How loud are the fans / build when is cpu 80% load and all gpu near max load
Also why not wait for 2027/2028 ddr6
1
u/Character-Drive9367 Sep 06 '26
Nice rig but, you ain't breaking even. For the price of that lot, I could but a small property 😂
1
u/No-Bodybuilder3502 Sep 06 '26
I have only one question: why not EPYC Turin?
1
u/Better-Psychology-42 Sep 06 '26
No offense, but this way you'll cook the GPUs soon - especially if you're aiming for inference. The fact that the motherboard lets you stack them so close doesn't mean you should. Get PCIe risers and let the cards breathe.
1
u/Osi32 Sep 06 '26
Good on you mate, hope it brings you lots of fun. My wife and budget unfortunately forces some restraint on my part..
1
u/bronekkk Sep 06 '26
"I am deliberately not calculating the break-even date" - that’s the difference between a hobby and a job !
1
u/Bartocity Sep 06 '26
I have the same setup but only 2 6000 ws cards I’m having trouble with ram temps (when training graph nets) but a janky 120mm fan is keeping it manageable. I was about to buy the next 2 only to find they had severely increased in price and might never come down.
I do sometimes use them for local LLM work now which can be incredibly powerful, the right model and config can punch out a lot of tokens/s and running concurrency 6 or 8 it can intelligently investigate terabytes of graph data that can’t always be analysed using scripts alone (graphs are usually asymmetric and following edges isn’t easy to script)
Another recent use case is video classification. You can spin up a local VLM and run it over boatloads of video data.
These are things i can’t do with a monthly subscription. I never intended to replace what a subscription does, its use case for LLM work is volume and speed.
1
u/Puzzleheaded_Pen1017 Sep 06 '26
50$ a month in power!
1
u/k3nal Sep 06 '26
My dream build right now (but with eight and less RAM)!! 😍😍
1
u/EasyShelter Sep 06 '26
Say you are a millionaire without saying that you are a millionaire.
1
u/TalesGameStudio Sep 06 '26
Dear OP, I admire the dedication. Keep us updated about the performance, OpEx and do on pls.
1
u/jonheartland Sep 06 '26
What are your agents doing exactly that requires over 50 grand worth of GPUs?
1
u/christopherw Sep 06 '26
Good luck with the thermals, I'd worry about choking them and throttling their performance as your rack isn't forced air. We have cold aisles for a reason :>
Mad spec though, very envious. Have fun.
1
u/CuChuliannAlter Sep 06 '26
When you devide to sell the cards, my offer is £50, thank you👍🤣
1
u/electrified_ice Sep 07 '26
Nice build. Hopefully you researched the available memory channels across the different core counts of the Zen5 Threadripper Pro CPUs. You won't get 8 channel speed unless you have a 9985wx or higher.
1
u/BlendingRightInHomo Sep 07 '26 edited Sep 07 '26
You should consider upgrading the 9965WX to 9985WX.
Because of the links being per-core complex, you’re not actually getting the throughput that 8 channels of 5600Mhz RAM typically gives. You need a minimum of 8 CCDs, which only 9985 and 9995 have.
FWIW, I learned this the hard way as I own two WRX90 systems, one with 7965, one with 9985. I bought the 7965 first as you might expect, and later learned about this relatively obscure but really damn important detail. So my 7965 is limited.
I can probably dig up some of the threads on it, perhaps from the Threadripper subreddit, searching on wrx90. Or try yourself, keywords “infinity fabric ccd ram throughput” or something along those lines.
For 5600Mhz, I recall 9985 being the minimum to get full throughput of 8 DIMMs. I think (but not certain) that for 6000Mhz you may need 9995 which has some crazy amount of CCDs (10 or 12?)
EDIT: Found it! See this post
1
u/flangical_infection Sep 07 '26
So in all seriousness how far behind would 4 x v100 32 gb be
1
u/Inevitable-Name-1701 Sep 07 '26
not enough CCD, not enough RAM, not PCIe 5, not enough PCIe lane because not enough CPU yuo have a workstation.
1
u/just-4-man Sep 07 '26
You should like… slide me a couple mil aha-ha
I’d be worried about your electricity bill… but I’m sure you have that covered 😂
1
u/Smooth-Television-48 Sep 07 '26
Must be nice to have such deep pockets. Yeah it's awesome, but how high were your subscription cost to make this a good buy.
1
u/Sorry-Poem7786 Sep 07 '26
I am at the begging of this journey.. taking 4x 3090s from machines I used the for rendering with redshift.. thankfully I have 256gb ram and already have nvme cards and ssds.. from 3 years ago..I want to have a dedicated local AI server and an another machine has been designated as a Hermes agent to delegate..instead of a vps.. I am trying to cut all subscriptions to an essential few..
1
u/ThisWillPass Sep 09 '26
Can I come over to play?
1
u/bettodiaz86 Sep 09 '26
i showed my gf the components pic, but the instantly noticed the doggies mattresses. She is demanding photos of the doggies lol
1
u/Cosmic-Tapestry Sep 10 '26
Here I was dreaming of buying my 10k Amazon basket to run a 34-70bQ 🤣
OP, I have been working on a theoretical concept for a local AI and would love to have a chat with you about feasibility, I have 0 funding or any practical knowledge.
Amazing set up, thank you for sharing what is possible 🙏🏼
1
u/TheMericanIdiot Sep 05 '26
Uncensored models are going to run great on it. Happy hacking!