Probably not worth $50.

Probably not. 8GB is tight for browsing these days, but 16GB won’t turn that Haswell into a photo-editing beast. Lightroom or GIMP will still feel sluggish because the CPU and old DDR3 speed are the real bottlenecks.

You’d likely see more improvement from a $50 SSD (if you haven’t already got one) or saving that cash toward a used OptiPlex with an 8th-gen or newer chip. The RAM upgrade helps, but it’s a band-aid on a machine that’s already past its prime for anything beyond basic email and YouTube.

Put that $50 toward a newer system – even a used one will feel like a bigger upgrade than doubling RAM on a Haswell.