Proxmox Host (Core Ultra 7 265K)
Identifier: Intel Core Ultra 7 265K on ASUS Pro WS W880-ACE SE Form factor: Proxmox server with GPU passthrough to Win11 VM Status: active
A Proxmox host running an RTX 5090 in passthrough to a Windows 11 VM. The CPU shows up in Geekbench as “QEMU Standard PC (Q35 + ICH9, 2009)” because the guest sees the virtual chipset, but the underlying CPU reports as Intel Core Ultra 7 265K (Arrow Lake, 20c). The VM was allocated 4 vCPUs and 16 GB RAM during testing — host motherboard and total host RAM are not visible to the guest.
Build & Cost
| Component | Spec | Cost |
|---|---|---|
| Host CPU | Intel Core Ultra 7 265K (Arrow Lake, 20c, LGA 1851) | $337.50 (2025) |
| Motherboard | ASUS Pro WS W880-ACE SE (LGA 1851, DDR5, PCIe 5.0, TB4, 4× M.2) | $449.99 (2025) |
| Host RAM | Crucial Pro 64 GB (2×32) DDR5-5600 CL46 | $159.99 (2024) |
| GPU | NVIDIA RTX 5090 32 GB | $1,999.00 (2025) |
| Total parts invested | $2,946.48 |
Per user policy, case / PSU / cooler are not tracked individually for piecemeal builds.
Geekbench AI Runs
All runs are RTX 5090 passthrough into a Windows 11 Pro VM. Score variance reflects different driver versions, power states, and thermal conditions across runs — the best numbers below should be used for ACI.
| Date | Single | Half | Quant | Result |
|---|---|---|---|---|
| 2026-01-24 | 36,140 | 50,470 | 27,963 | 428175 |
| 2026-01-23 | 35,851 | 50,183 | 27,827 | 427800 |
| 2026-01-24 | 35,076 | 48,635 | 27,261 | 428196 |
| 2026-01-24 | 34,718 | 48,382 | 27,311 | 428178 |
| 2025-12-27 | 29,750 | 41,817 | 26,121 | 412119 |
CPU baseline (inside VM)
| Backend | Single | Half | Quant | Result |
|---|---|---|---|---|
| ONNX / CPU | 2,471 | 1,362 | 5,437 | 412123 |
AI Capability
- Best Single / Half / Quant: 36,140 / 50,470 / 27,963
- ACI: 775.4 — Tier S
- **GPU 2.58 ($1,999 / 775.4 × 100)
The previously-attributed 5090 run 470447 (Single 44,345) is actually from the Lenovo P8 Threadripper host — its user notes say “proxmox vm + 5090” but the CPU reports as Threadripper PRO 9965WX, not Ultra 7. That run has been moved.
Within this Ultra 7 host, the spread between best (36,140) and worst (29,750) suggests a thermal/power scaling issue worth tracking. VM passthrough also imposes a small overhead vs bare metal.
Notes
- Host hardware identification still needed — Geekbench cannot see through QEMU. Run
dmidecode -t baseboard -t memoryon the Proxmox host directly. - Score variance likely tied to NVIDIA driver versions across the Jan 23–Jan 24 cluster. Worth pinning a known-good driver.
See Also
- Benchmark Methodology
- Proxmox: Lenovo P8 Threadripper — same passthrough strategy, different host, hosts the PRO 6000 Blackwell
- MSI Codex R — same RTX 5090 model, bare metal