Trying out (for science) Windows 11 on a 15 year old Compaq Presario V3000, what's most probably the oldest Intel based laptop that can technically run it (earlier ones either don't support
4GB DDR3-1333 RAM Memory Upgrade for The Compaq HP Presario CQ56-115DX (Genuine A-Tech Brand) at Amazon.com
4Gb (1X4Gb) Memory RAM Compatible with Compaq Presario Cq56-219Wm Ddr2 Sodimm By CMS (A42) - Computer Memory Solutions
4Gb (1X4Gb) Memory RAM Compatible with Compaq Presario Cq56-219Wm Ddr2 Sodimm By CMS (A42) - Computer Memory Solutions
CMS 8GB (2X4GB) DDR3 8500 1066MHZ Non ECC SODIMM Memory Ram Upgrade Compatible with Compaq Presario Cq56-109Sl, Cq56-109So - A35 at Amazon.com
8gb ram upgrade for compaq presario cq56 - Newegg.com
A-Tech 4GB RAM for COMPAQ PRESARIO CQ56-219WM | DDR2 800MHz SODIMM PC2-6400 200-Pin Non-ECC Memory Upgrade Module at Amazon.com