I use a fanless ITX board with onboard processor with Win10 for Excel development and application maintaining: 4x2GHz and 8GB Ram with a used SSD. To keep it cheap I use a pico power supply - consider how much power you need. Here the sources from my notes (2019):
board 4x2,08GHz 50€
https://www.ebay.de/itm/Mitac-PD14RI-D-N3150-Intel-D2500HN2-Mini-ITX-Mainboard-Motherboard-FANLESS-/401438905676?hash=item5d779f954c
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8GB DDR3 53€
https://www.mindfactory.de/product\_info.php/8GB-Kingston-ValueRAM-DDR3-1333-DIMM-CL9-Single\_800875.html -
Pico 28€
https://www.ebay.de/itm/picoPSU-80-DC-DC-80-Watt/162499959144?hash=item25d5c09968:g:TYIAAOSwjL5ZCEwq -
externes 12V Netzteil (60W) 8,39€
https://www.ebay.de/itm/Netzteil-60W-12V-5A-fur-LCD-TFT-Monitor-LED-Strips-NAS-Festplatten-Pico-PSU/292553664098?hash=item441d8ea662:g:ZxkAAOSwMNVa8D5a
https://www.ebay.de/i/292553664098?ul\_noapp=true
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