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MaxUpgrades hardware upgrades for Apple hardware.

YouTube - Surprise! My Dad Revisits Our First Mac from 1990 on 2022-11-12, by Mac84.

YouTube - Can Linux Save a 16 Year Old iMac? on 2023-07-30 by Action Retro.

Running Mac OS Sonoma on a Trash Can Mac Pro? Easier and cheaper than you think! on 2024-01-08 by Jon Obst.
Can This Decade-Old Mac Pro Compete With Apple Silicon? on 2022-11-11, by This Does Not Compute.
Installing Linux on Apple's Stupid Trashcan exploring Bazzite Linux on a Trashcan Mac Pro, on 2023-09-09, by Action Retro.
The Ultimate Linux Gaming Trashcan on 2024-09-24, by Action Retro. (Spoiler alert: Windows 10 and the AMD driver can use CrossFire to use both D[3,5,7]00 GPUs.

Modern Ubuntu is KILLER on old Intel Macs! on 2023-07-08, by Action Retro.

By Action Retro on YouTube:

• Can an iMac G3 with OpenBSD be my daily driver? on 2022-01-15
• Installing OpenBSD on the Fastest iMac G3 on 2023-11-11.

YouTube - The Power Macintosh G4 (1999) by 65scribe.

Sonnet G5 Jive allows adding an extra three hard drives and a SATA controller to a Power Mac G5.

YouTube - Upgrading the "Jurassic Mac" Quadra 700 to Unspeakable Levels! on 2021-05-22, by Action Retro.

DOOM, but BeOS on 2023-04-09, by Action Retro.