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Compute guide

Enterprise vs consumer GPUs for LLM inference: a comparison matrix

GeForce RTX 5090 vs NVIDIA RTX PRO Blackwell and L40S for local LLM inference: VRAM, bandwidth, ECC, power, cooling, form factor, virtualisation and licensing, with a decision guide.

Draft dated 1 October 2026 · 10 min read · Published by Green Racks Pty Ltd

Close-up of a dark circuit board with gold pads
IllustrativePhoto: Vishnu Mohanan / Unsplash

Draft pending approval. General information only, not legal, financial or electrical advice. Facts were checked against the linked primary sources on the draft date; verify before relying on them.

Every local AI project eventually reaches the same fork. A GeForce RTX 5090 has 32 GB of fast memory and costs a fraction of a data-centre card. Why would anyone pay more for a “professional” or “enterprise” GPU?

The honest answer is that it depends on where the card will live, how long it will run, and who will support it. This guide sets the main NVIDIA options side by side, using figures from NVIDIA’s own spec pages, and explains which differences matter for inference. We have deliberately left prices out. They move weekly and depend on the distributor, so Compute Vault lists them as “Price on request”.

The comparison matrix

GeForce RTX 5090RTX PRO 4000 BlackwellRTX PRO 4500 BlackwellRTX PRO 6000 Blackwell Max-QRTX PRO 6000 Blackwell ServerL40S
ClassConsumerWorkstationWorkstationWorkstationData centreData centre
ArchitectureBlackwellBlackwellBlackwellBlackwellBlackwellAda Lovelace
Memory32 GB GDDR724 GB GDDR7 ECC32 GB GDDR7 ECC96 GB GDDR7 ECC96 GB GDDR7 ECC48 GB GDDR6 ECC
Bandwidth1,792 GB/s672 GB/s896 GB/s1,792 GB/s1,597 GB/s864 GB/s
Max power575 W140–145 W200 W300 Wup to 600 W (configurable)350 W
CoolingOpen-air (Founders Edition)Active, single slotActive, dual slotActive, dual slotPassivePassive
MIGNoNoNoNot listed on spec pageUp to 4 × 24 GBNo
vGPUNoNot listed on spec pageNot listed on spec pageNot listed on spec pageYes (vWS, vPC/vApps)Yes
Datacenter driver licenceNo (GeForce EULA)Workstation driversWorkstation driversWorkstation driversYesYes

Sources: NVIDIA spec pages for the RTX 5090, RTX PRO 4000, RTX PRO 4500, RTX PRO 6000 Max-Q, RTX PRO 6000 Server Edition and L40S; Lenovo Press product guide for RTX PRO 6000 Server Edition vGPU support. RTX 5090 bandwidth from PNY’s GeForce linecard. Partner-board GeForce cards vary in power and cooling. Always confirm against the current sheet for the exact SKU.

What actually matters for inference

1. VRAM capacity decides what fits

A model that does not fit in GPU memory either does not run or runs painfully slowly with layers offloaded to system RAM. As a rough guide, weights take about 2 bytes per parameter at 16-bit and about 0.5–0.6 bytes per parameter at 4-bit, plus room for the KV cache. Our local LLM guide has a fuller sizing table. In short:

  • 24 GB (RTX PRO 4000) comfortably runs 7–8B models at 16-bit, or ~30B models at 4-bit with modest context.
  • 32 GB (RTX 5090, RTX PRO 4500) adds room for longer context and more concurrent users at the same model sizes.
  • 48 GB (L40S) is the entry point for 70B-class models at 4-bit.
  • 96 GB (RTX PRO 6000) runs 70B-class models at 8-bit with generous KV cache, or several smaller models side by side.

Multiple cards can split a model (tensor or pipeline parallelism), but none of the cards in this table supports NVLink, so the split runs over PCIe. That works well for inference servers such as vLLM, at some cost in efficiency.

2. Memory bandwidth sets generation speed

During token-by-token generation, the GPU reads the active weights from memory for every token. Single-stream speed is therefore roughly bounded by bandwidth ÷ model size. Here the RTX 5090 is very strong: its 1,792 GB/s matches the RTX PRO 6000 Max-Q, and it is more than double the RTX PRO 4000’s 672 GB/s.

That is the consumer card’s real appeal. For a single developer running a model that fits in 32 GB, it is fast.

3. ECC and long-running reliability

The professional and data-centre cards list ECC (error-correcting code) memory. The RTX 5090 spec page does not. ECC detects and corrects single-bit errors caused by electrical noise, heat or cosmic rays. On a desktop used a few hours a day, the risk is small. On a server answering requests around the clock for years, silent memory errors become a real source of corrupted outputs and unexplained crashes. ECC also exposes error counters (through nvidia-smi), so you can see a card degrading before it fails.

4. Power and heat per useful gigabyte

Compare memory per watt at the default limit:

  • RTX 5090: 32 GB / 575 W ≈ 0.06 GB/W
  • RTX PRO 4000: 24 GB / 140 W ≈ 0.17 GB/W
  • RTX PRO 4500: 32 GB / 200 W ≈ 0.16 GB/W
  • RTX PRO 6000 Max-Q: 96 GB / 300 W ≈ 0.32 GB/W
  • L40S: 48 GB / 350 W ≈ 0.14 GB/W

For inference workloads limited by memory capacity, the professional cards hold far more model per watt. That matters twice in a rack, once for power and once for cooling. It also determines whether a box runs on a standard office circuit at all. See our PSU sizing guide.

5. Cooling design must match the chassis

This is the difference people discover the hard way.

  • Open-air consumer coolers exhaust heat into the case. They suit a desktop tower with good case airflow, and they suit a rack-mount server badly: cards sit side by side, starve each other of air, and recirculate hot exhaust.
  • Active workstation coolers (RTX PRO 4000/4500/6000 Max-Q) are designed to stack in workstations. The single-slot RTX PRO 4000 is particularly dense.
  • Passive data-centre cards (L40S, RTX PRO 6000 Server Edition) have no fans at all. They depend on high-pressure server fans pushing air front to back through the heatsink. In a desktop tower they will overheat and throttle within minutes.

Pick the card to suit the chassis and the room, not the other way around.

6. Virtualisation and sharing

If several teams or tenants need to share a GPU, the data-centre cards support NVIDIA virtual GPU software. The RTX PRO 6000 Server Edition also supports Multi-Instance GPU (MIG), which splits one card into up to four isolated 24 GB instances, each with its own memory and compute. For an internal platform team that wants hard isolation between workloads, that is a significant feature. Consumer cards have neither.

7. Licensing and support

NVIDIA’s GeForce driver licence (section 2.8 in the current Linux driver licence text) states that GeForce or Titan software “is not licensed for datacenter deployment”. The licence does not define “datacenter” in a way that resolves every case, so get your own advice. In any case, a GeForce card in a colocation rack serving commercial customers is the scenario the clause appears aimed at. Professional and data-centre cards also come with longer driver support branches, enterprise warranty channels, and certification in OEM servers from Dell, HPE, Lenovo and Supermicro.

A decision guide

Choose a GeForce RTX 5090 if you are a single developer or a small team experimenting on a desktop, models fit in 32 GB, downtime does not matter, and the card stays in your own workstation rather than a commercial data-centre deployment.

Choose an RTX PRO 4000 Blackwell if you want the most efficient way to put 24 GB of ECC memory into a workstation or small server, need many cards in a dense chassis (it is single-slot and draws about 140 W), or want to serve 7–14B models to an office reliably. It is also the card family behind Green Racks’ hosted AI tiers (listed as NVIDIA Pro 4000).

Choose an RTX PRO 4500 Blackwell if you need 32 GB with ECC in a dual-slot workstation at about 200 W.

Choose an RTX PRO 6000 Blackwell Max-Q if you need 96 GB in a workstation, want to run 70B-class models on a single card, and want to stay at a manageable 300 W per card.

Choose an RTX PRO 6000 Blackwell Server Edition or L40S if the card is going into a proper rack server with front-to-back airflow, you need vGPU or MIG (RTX PRO 6000), and the system will run as a production service.

Common mistakes

  1. Buying on compute TFLOPS for an inference project. For most LLM serving, memory capacity and bandwidth matter more.
  2. Putting passive cards in a tower. They need server airflow.
  3. Ignoring the PSU and circuit. Four 575 W cards is a 2.3 kW GPU load before anything else, which is the entire capacity of a standard Australian 10 A outlet.
  4. Not planning for heat. Every watt you buy has to be removed from the room.
  5. Assuming “it worked on my desk” means “it will work in production”. Continuous operation, ECC, monitoring and support are what separate the two.

Where to run it

A GPU that throttles in a hot comms cupboard is wasted money. If you are buying professional cards for production inference, put them somewhere with conditioned power and cooling. Green Racks’ Osborne Park, WA facility offers 2N UPS (150kVA), dual A/B feeds per rack, N+1 cooling and NOVEC fire suppression, and you can compare the running cost against keeping the box in your office.

Sources

FAQ

Can I use a GeForce card in a server for inference?

Physically, yes. But NVIDIA's GeForce driver licence states that GeForce or Titan software is not licensed for datacenter deployment. Consumer cards also lack ECC on the spec sheet, use open-air coolers designed for desktop cases, and have no vGPU support. Check the licence terms with your legal adviser before deploying GeForce cards in a data-centre setting.

Which matters more for LLM inference: VRAM or compute?

VRAM capacity decides which models fit at all, and memory bandwidth largely sets single-stream generation speed. Compute (Tensor Core throughput) matters most for prompt processing, large batches and training.

What is the difference between the RTX PRO 6000 Server Edition and Max-Q?

Both have 96 GB of GDDR7 with ECC. NVIDIA lists the Server Edition at up to 600 W (configurable) with passive cooling for server chassis and 1,597 GB/s bandwidth, and the Max-Q Workstation Edition at 300 W with an active cooler and 1,792 GB/s bandwidth.

Is ECC memory necessary for inference?

It is not strictly necessary, but ECC detects and corrects single-bit memory errors that would otherwise silently corrupt results or crash long-running jobs. For production services that run continuously, it is a meaningful reliability feature.

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