Maybe adding a third fan, the bottom “radiator” will act as a simple gasket?
I have not installed any bottom intakes yet. But will install 3, that deciding on what fans to buy.
Having second thoughts about the shroud. It’s getting too close to the 2 slot gpu and i plan to buy a thick gpu in January.Would probably help but I guess the only way you'd know for sure is to make some smoke and see where it goes - something like this:...but that's probably massively overthinking it (I have form ) and ultimately what's going to matter is his temps and how loud it is.
The original case fan mounts are hardly sealed in the 1st place. Ghe rpm will be so low that noise is negligible.
We’ll see when I get new fans.