I just bit the bullet to buy an R9700 in case prices shoot up for AMD GPUs because I missed my chance on NVIDIA already, however I don’t have anything to put it in. My current NAS is an Aoostar 4 bay (currently only 2 bays with only 6 of 12TB used) with no real way to upgrade its hardware other than adding more storage. I’d like to move it to my parent’s house as an offsite backup and have something more upgradable at home.
I’ve never built a computer before. Farthest I’ve gone is upgrading RAM or SSD, so the hardware side of things makes me nervous. I’m thinking the cheapest and easiest way to get started is to find a used enterprise workstation to drop it into to get started. Claude recommended a Lenovo ThinkStation P620, but a P520 is more in my current price range (sub $1000).
Is there anything I should be looking for? Will that gpu actually work with that tech? What do I not know I need to check? Claude said there were already several internal 3.5" drive bays and SATA ports to add drives to for the NAS storage. Anyone able to confirm that?
My current NAS runs Unraid. I’m not sure what OS I would run on this, other than definitely Linux. I’m familiar with Fedora, Ubuntu, and Unraid. It would be for local LLM learning and development, my NAS storage, a variety of container/services like Jellyfin and immich, and maybe a game server.
The first thing to consider is that the P520 only supports PCIE 3.0, which is going to hobble you somewhat if you later upgrade to dual R9700s (which is the ideal configuration). Of course, you’d also need two x16 slots for that in the ideal situation, so you’re looking at Xeons or Threadripper.
Secondly, you’d have to make sure that the workstation you buy has enough cooling to feed the card with cool air, and that the PSU has ~350-400W headroom over the hardware that’s already in it, and that the PSU has enough spare connectors to put a 12VHPWR adapter on there (usually 2 x PCIE power, or 2 x EPS/CPU power).
Alternatively, there’s the compromise option - a Ryzen 5x00 CPU and an X570 board (like the ROG Strix X570) that supports x8/x8 split on the two physical x16 slots. That’d cover you for an intermediate point in the upgrade path later on. The bonus is that this should cost you a lot less than $1k, although you’d still have to get RAM/SSD/etc.
Since you have only one card, and given the price of memory and storage these days: If this has been a new build dedicated to that R9700, I’d have recommended any motherboard with preferably PCIe 5.0 x16, any reasonable processor that fits the motherboard and has the PCIe 5.0 bus support, as much RAM as affordable, and a m.2 SSD. How much you need depends on what you intend to do. I do not know enough about used workstations to give any useful advice there.
What kind of experiment do you have in mind? For inference with Radiance (the latest backend for that specific card,) Qwen3.8-Flash-Next at W4A8 just about fits on the card plus 48GB RAM leaving a few GB free; Qwen3.8-27B fits on the card at W4A4, but was said to have problems with quantization damage. W8 also fits, but not with a context window useful for current coding agents with non-toy tasks.
NAS drives would cut into that budget. Would you rather have more storage or more memory?
The real barrier these days is the cost of memory. Next, is a cost of M.2 SSDs. If you’ve never built a PC before, you might be better buying a used one. However, to run a single R9700, you need a large PSU of 750W or more. That is your largest barrier to a used PC as most used pre-built PSUs are much lower. I have seen spikes over 450W on my R9700s. There’s undervolting you can tweak to limit this to around 275W, but you’d want a PSU that can handle the full load during setup and tuning + the rest of the system.
As mentioned above, the next hurdle is PCIe speed of 4.0 minimal, 5.0 if you can afford it. 3.0 will still work for a while, just plan on grabbing a coffee while you wait for large prefills.
As far as specs, all you need to get started is 16GB but 32GB gives you some headroom and even to run some larger MoE models. 800W PSU, 1 TB SSD is fine. Gen4 preferred, Gen5 great if you can afford it.
Do you have a Microcenter near you? I’ve been buying several of their “Bundle Deals” for friends for builds for $200-$700. Add a cheap M.2, PSU, and case and you’re good. I’m also a big fan of the AMD AM4 platforms (the DDR4 bundles there) as it’s more than enough to run the R9700, and you get way more bang for your buck over the AM5 in those bundles. They can even assemble for you, or assemble WITH you, for a fee.
Alternatively, ebay and Craigslist is where I’ve been picking up most other parts. CL is especially fruitful because those are the people that don’t want to ship entire PC builds. Feel free to post a build here for us to vet.
I know the budget limitations are not ideal. I could go over for a really good deal that would have better longevity, but I was hoping to get it in something and working sooner rather than having it just sit in the box until I could get all the best tech. It makes me nervous to not be able to check it doesn’t have any issues for an extended period of time. The budget can really grow if you keep saying “well, a couple more hundred are worth it”, so I am trying to be firm with myself to prevent going too much over budget.
Unfortunately I don’t live anywhere near a MicroCenter. I’ll be in Denver around mid December or early January, so maybe I could grab something then. I’m not against waiting to see if there are any good deals over Black Friday/Cyber Monday and building my own, but I need an idea of what to actually look for.
I’ve been going through the pricing out with the idea of doing a DDR4 build that could support a second card, but realistically, I can’t see that happening in the next year, so perhaps it is better to not limit myself with that right now?
I’ve been looking on Craigslist and Facebook Marketplace for used options, and not having good luck. I’ve been trying to look on ebay, but it is hard to know what I need to search properly. I was originally thinking I could just upgrade the PSU on the Lenovo workstation until I realized they are proprietary and not really upgrade-able, so that finished that thought off.
For what it’s worth, folk in the modding community have used standard ATX PSUs in these machines, there’s an adapter for the motherboard. Of course, that way lies a fair old rabbit hole
Personally I would try to keep your workstation and NAS totally separate and not try to do everything in one box.
Threadripper would be “ideal” as depending on the version and board you can get 2ea x16 slots and 2ea x8 slots, possibly 3ea or 4ea full x16 slots on some of the TRX50 boards or even more slots on a WRX80 or newer TR Pro motherboard, just read MB manuals carefully to see what it does with certian CPUs… But you will have kinda high power draw, expensive board & CPU (Careful about pre-made workstations like Lenovo that lock down CPUs and or have kinda annoying non standard parts that make upgrades a pain)… But the costs are all around pretty high for TR.
You can run a pretty normal consumer CPU and Motherboard. If you want to just run one card an ITX board can work but will lock you out from a 2nd GPU, a full size ATX board makes more sense, there are plenty of options out there, but lots of give and take. I don’t know if there are any DDR4 LGA 1700 motherboards with PCIe 5.0 speed primary slots (ideal configuration would be 5.0 x8 and 5.0 x8 so the R9700 has half the max PCIe bandwidth). I’m pretty sure you will be stuck buying DDR5 if you want to have PCIe 5.0 speeds. Going DDR4 will get you cheaper to source used RAM, will be limited to PCIe 4.0 speeds, but a lot of LGA 1700 & AM4 motherboards available with 2ea 4.0 x8 primary PCIe slots for GPU.
PCIe 5.0 x16 has a theoretical max bandwidth of about 64GB/s, cutting the lanes in half to x8 gets you around 32GB/s. Going to PCIe 4.0 x16 is also 32GB/s, where PCIe 4.0 x8 is half that again at 16GB/s. Multi GPU will typically suffer a good bit in particular tasks like loading models, or communication between GPUs.
I have a pretty current Threadripper build with 4ea R9700 GPUs powered by a Silverstone 2500Rz (at 1650W due to 120v), around 150W idle power draw. I also have a little ITX build with a minisforum BD790i mobile CPU ITX board, laptop memory, and an RTX 5060Ti 16GB card for Comfy UI and lighter LLM use.
You REALLY should run whatever rig on a good UPS, or at minimum a decent surge protector.
