Overclocking
The ASRock Z490 AQUA showed quite a bit of headroom for overclocking, at least for short runs of wPrime. I was able to achieve 5.3 GHz at 1.38 V core voltage. However, longer runs were not stable. Overclocking is largely limited by temperature since the 10-core Intel Core i9-10900K will overpower any ambient cooling solution. Depending on settings, the system will either crash or severely drop frequency.
For memory overclocking, the ASRock Z490 AQUA did well, reaching 4000 MHz stable at XMP timings and voltages on my Trident Z Neo kit.