Getting ESXi installed is the easy half of a whitebox build. Where your virtual machines actually live — and how fast and how safely they live there — is decided by storage choices the installer mostly leaves to you. This page works through them without the marketing.
A hypervisor turns one computer into many, and every one of those virtual computers reads and writes the same physical disks. That makes storage the shared bottleneck and the shared risk of the whole lab. Consumer hardware adds its own wrinkles: motherboard RAID that ESXi cannot see, bargain NVMe drives that wilt under sustained writes, and thin provisioning that lets you promise VMs more space than exists. None of these are reasons to avoid a whitebox — they are reasons to choose the layout with your eyes open.
👆 All three work. The question is which of your VMs deserve SSD speed and which only need cheap capacity (illustration).
By default ESXi splits its boot disk into a system area (ESX-OSData) and a VMFS datastore for your VMs. Sharing one disk is perfectly acceptable in a lab — the host itself barely touches its system area while running. The best-value upgrade a whitebox can get is a second SSD dedicated to VMs: the host disk and the VM disk then fail independently, reinstalling ESXi never endangers the VMs, and busy VMs stop competing with the host for the same flash.
ESXi carries native NVMe support, and a good NVMe drive is the fastest home a VM can have. Three honest caveats. First, a few consumer controllers behave oddly with ESXi — if a drive vanishes from the installer, check the BIOS storage mode before blaming the drive. Second, bargain DRAM-less drives post wonderful benchmark numbers and then slow down painfully during long writes, which is exactly what installing VMs does. Third, NVMe drives run hot in a closed case; a throttling drive looks like a mystery performance problem. None of this forbids consumer NVMe — it just rewards buying a decent one.
A SATA SSD is slower than NVMe on paper and completely adequate in practice for a handful of home lab VMs — the difference is hard to feel outside benchmarks. Spinning disks are the opposite trade: poor homes for VMs you use daily, but excellent, cheap warehouses for ISO installers, templates and backups. A sensible whitebox often ends up with all three tiers: NVMe or SATA SSD for running VMs, hard disk for the library.
Most motherboard "RAID" — Intel RST and its cousins — is software RAID driven by a Windows driver. ESXi cannot see those volumes; it sees the individual disks, or sometimes nothing sensible at all. Real protection in ESXi terms means a supported hardware RAID controller, which most custom PCs do not have. So plan as a single-disk host: no RAID safety net, which makes the next sentence the most important on this page — your backup routine is your RAID. Export or copy important VMs to another device on a schedule, and a dead disk becomes an inconvenience instead of a funeral.
ESXi lets you provision thin disks: a VM can be promised 200 GB on a datastore that physically holds 120 GB, growing only as it writes. It is a wonderful feature right up to the moment every promise comes due at once — a datastore at 100 percent pauses VMs mid-work. Snapshots feed the same trap, because a snapshot grows with every change while it exists. Leave real headroom, delete snapshots when their job is done, and glance at datastore usage weekly. Full is the one storage number that never fixes itself.
See the storage choices in the video as the build takes shape — then use this page to decide your own layout before your first VM.
▶️ Watch Full VideoBecause Intel RST is host software RAID — the combining is done by a driver inside Windows, and ESXi has no such driver. To ESXi the volume simply does not exist. Set the BIOS storage to plain AHCI mode and let ESXi use the individual disks, or fit a supported hardware controller.
Treat USB as installer media and emergency storage only. USB datastores are unsupported, fragile, and slow in ways that corrupt your opinion of the whole platform. A small internal SATA SSD costs little and is better in every dimension.
The installer needs surprisingly little, but give it room to be comfortable: a 128 GB or larger SSD lets ESXi create its system area and a local datastore with space to spare. Larger is about the VMs, not the host.