PC Master Race

1. DDU to remove all your old drivers
2. Download latest drivers from AMD.com
3. Familiarize yourself with the driver software and features (and the few that are missing).

Did you consider a new card (even an Arc card)? Or was the used 5600 a really good deal?

Resizable Bar (aka Smart Access Memory for AMD) is a good thing for any gpu really, I haven't heard of it having any downsides. You should also use Freesync if you have it, and if not maybe Enhanced Sync idk. I also like turning on Anti-Lag and Contrast Adaptive Sharpening in the driver settings.

Run a full uninstall of your video drivers! THEN install AMD's software and drivers just to avoid any issues there.

Doing some quick searching, I don't think SAM (AMD's name for resizeable BAR) is available on the 5000 series, just 6000 and up. You'd need an AMD CPU as well.

I've been running a 6700XT with an Intel CPU and it hasn't been bad, but not great either. I've had trouble with the most recent graphics drivers; I tried to update in May and had to deal with a bunch of blackscreens before finally reverting to November's drivers. Luckily AMD has old drivers available directly on their website.

Messing with the GPU's performance settings within Adrenaline (AMD's version of geforce experience) is also super buggy, only working for a few hours at best before crashing and reverting. I'm talking anything physical, from overclocking to just increasing ambient fan speeds. Their bug reporter is also terrible! Changing render settings for specific games has worked fine, as well as deactivating the ingame overlay, but while I think you should play with it just to see how it works for you, I can only recommend using Adrenaline as a temperature monitor.

At the end of the day though it's not much buggier than my ancient dual 680 setup was lol, and it's like half the price of Nvidia stuff so I'd say you probably won't regret the purchase