So, You Have Two GPUs and a Big Idea?

Thinking of building a homelab to train a custom cybersecurity AI? Here’s a practical guide on the hardware you’ll need to build around your GPUs.

So, you’ve got your hands on some serious hardware—maybe a couple of powerful GPUs—and an idea is sparking. You’re thinking about building your own homelab to train a custom AI, maybe one that’s an expert in cybersecurity.

That’s a fantastic project. It’s the kind of thing that’s not just for fun, but could actually help you in your work. I’ve been seeing more people get curious about this, so I thought I’d walk through what it actually takes.

Let’s imagine you’ve got two NVIDIA Quadro RTX 6000s. That’s a pretty amazing starting point. The big question is: is that enough, and what else do you need to bring your idea to life?

First, Let’s Talk About Those GPUs

The heart of any AI training rig is the Graphics Processing Unit (GPU). It’s all about the VRAM—the GPU’s own super-fast memory. When you’re training an AI model, the model itself and the data you’re feeding it have to live in that VRAM.

Each RTX 6000 has a generous 24 GB of VRAM. With two of them linked together (using something called NVLink), you can get them to act like a single GPU with 48 GB of VRAM.

So, are they enough? Yes, absolutely. For a homelab, 48 GB of VRAM is a massive amount of room to work with. You won’t be building the next GPT from scratch, but you can definitely fine-tune some very powerful open-source models on a huge amount of cybersecurity text. This is more than a good start; it’s a great one.

But a Homelab is More Than Just GPUs

Your GPUs are the star players, but they can’t win the game on their own. They need a solid supporting cast of hardware. If the rest of your system can’t keep up, your powerful GPUs will just be sitting around waiting. This is called a bottleneck.

Here’s what you should think about for the rest of the build:

CPU (The Traffic Cop)

Your CPU’s job is to get data ready for the GPUs. It handles tasks like loading data from your storage, pre-processing it, and feeding it into the training pipeline. You don’t need the most expensive CPU on the market, but you don’t want to skimp here either. A modern processor with a good number of cores (like an AMD Ryzen 7/9 or an Intel i7/i9) will prevent a lot of headaches.

Motherboard (The Foundation)

This is what connects everything. Your main priority is finding a motherboard with at least two PCIe x16 slots. These are the slots your GPUs plug into. Pay close attention to the spacing—you need enough physical room between the cards for air to flow. You’ll also want to make sure the motherboard supports the NVLink bridge needed to connect your two RTX 6000s.

RAM (The Workspace)

While your GPUs have their VRAM, your system needs its own RAM for the CPU to work with. Data gets staged here before it goes to the GPU. For an AI project, more is better. I’d suggest starting with at least 64 GB, but 128 GB is a safer bet if you can swing it. It feels like overkill, but you’ll be glad you have it when you’re working with massive datasets.

Storage (The Library)

Training AI means reading a lot of data, and doing it quickly. Your storage needs to be fast.
* For your OS and active datasets: Get a fast NVMe SSD. At least 1 TB, but 2 TB is better. This is where you’ll store the data you’re actively using to train your model.
* For everything else: You can use a larger, slower hard drive (HDD) for archiving old models, storing raw data, and general file storage.

Power Supply (The Power Plant)

Don’t underestimate this. Two power-hungry GPUs, a capable CPU, and all your other components need a lot of clean, stable power. An underpowered PSU can cause random crashes that are a nightmare to debug. For a build like this, look for a high-quality PSU with at least a 1200W to 1500W rating. Look for an 80+ Gold or Platinum efficiency rating—it’s a sign of quality.

It’s Not Just About the Hardware

Building the machine is the first step. The next, and arguably harder, step is the project itself. You want to train an AI on “most major cybersecurity literature, tooling, policy work, etc.”

That means your real challenge will be collecting and cleaning a high-quality dataset. Where will you get this data? Think about sources like:

  • Academic papers from sites like arXiv
  • Security advisories and vulnerability databases
  • Documentation from open-source security tools
  • High-quality security blogs and articles

Curating this data is a massive task, but it’s what will make your AI unique and useful. You’ll likely be taking a powerful open-source model (like Llama 3 or Mistral) and fine-tuning it with your custom cybersecurity library.

So, is it possible? One hundred percent. It’s a challenging road, but you’d learn an incredible amount along the way. And starting with two strong GPUs gives you a serious head start. Just remember to give them the team of components they deserve.