AOOSTAR MACO AMD R7 6850H Mini PC (8C/16T 4.70Ghz) with LPDDR5 6400Mhz 24GB RAM Without SSD/OS,3 *M.2 Slots; Dual 2.5G LAN; LAN Dual USB4; Supports Quad-Screen Display

The absolute best option I've seen for a starter server is the Aoostar Maco R7. You get a decent 8c/16t CPU with an ok integrated GPU, plus 24GB of LPDDR5 6400, all for only $339 USD on Amazon right now. That CPU with that zippy RAM will outperform anything else near that price point. But you'll need to source some m.2 nvme drives because it doesn't come with any. https://a.co/d/08oWulA7