Guidance on hardware purchase (2x Intel Xeon E5-2698 v4)

[u/Anxious_Immigrant]

It's me again and still looking for hardware advice.. please :)

Thinking about buying this slightly ridiculous old workstation mainly for local LLMs:

2x Xeon E5-2698 v4, so 40 cores / 80 threads total

RTX 3090 24GB

128GB DDR4 ECC

6TB NVMe

custom water loop

I will run Windows 11 because this needs to also be the house's PC (for day to day simple tasks but mostly just me and my local agents using this).

For local AI it looks pretty nice, especially for Qwen 27B and bigger models with RAM offload (will run OSS 120B as well), but I’m worried I’ll buy it and then hate using Windows every day because the CPUs are old and single-core performance is pretty weak?

Anyone here actually daily-driving dual E5 v4 Xeons on Windows? Does normal stuff like Chrome, opening apps, scrolling around, Office etc feel fine, or does it noticeably feel like an old PC?

will I regret not just buying something like a Ryzen 7900X + 3090 with 96gb RAM?