If the kid didn't need a monitor, kb & mouse, it would be easier to hit the $600 budget. https://turbofuture.com/c...Desktop-Computer-Build
The site lists AMD and Intel budget system for $600 (no monitor, kb or mouse).
Another build i found.
PCPartPicker part list: https://pcpartpicker.com/list/2jrKkd
Price breakdown by merchant: https://pcpartpicker.com/list/2jrKkd/by_merchant/
CPU: AMD - Ryzen 3 2200G 3.5GHz Quad-Core Processor ($98.69 @ OutletPC)
Motherboard: Gigabyte - GA-AB350M-DS3H Micro ATX AM4 Motherboard ($49.99 @ Amazon)
Memory: Team - Vulcan 8GB (2 x 4GB) DDR4-3000 Memory ($70.98 @ Newegg)
Storage: Kingston - A400 240GB 2.5" Solid State Drive ($39.99 @ Amazon)
Case: Cooler Master - MasterBox Q300L MicroATX Mini Tower Case ($39.99 @ Amazon)
Power Supply: Corsair - CXM (2015) 450W 80+ Bronze Certified Semi-Modular ATX Power Supply ($29.99 @ Newegg)
Keyboard: Redragon - K552 Wired Gaming Keyboard ($29.99 @ Amazon)Total: $359.62
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2018-10-08 19:17 EDT-0400
*Some AMD B350 chipset motherboards may need a BIOS update prior to using Raven Ridge CPUs. Upgrading the BIOS may require a different CPU that is supported by older BIOS revisions