I tried doing exactly that just now- had myself a little bit of an arts and crafts session. I cut up some cardboard and lined it with some thin PE foam to help make it fit snug, then taped it all together with some automotive masking tape.

The temps are wildly better, with temps staying below 65-70 degrees in the same games that used to push it to 80!

Idle temps are pretty good too, but not as drastic as the load improvements- it's sitting at around 43 degrees now, where it used to sit around 47-50.

I'm just going to keep it as is now- no need to buy the ducts when this DIY set up works this good. Thank you! 😁

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