I have the subject line Antec case http://www.antec.com/product.php?id=1756&lan=uk which is now quite long in the tooth but it performs the role of a Windows 7 HTPC case quite well. Recently I upgraded most of my PCs internals from an E8500 Core 2 Duo to an i7 6700K based machine as I wanted better game performance but I'm still running Win 7 Home Premium (just the 64 bit version now) as I have a TV card and optical drive etc so I need my Windows Media Centre - irrespective of the way Microsoft want me to go! When I went to install the Motherboard (with CPU Cooler pre-attached), I found the plastic CPU cooler 'X bracket' under the motherboard meant the motherboard couldn't sit low enough to sit on the standoffs so I cut a square hole in the base of the case and hey presto it all fitted together with the X shaped plastic bracket about flush with the outside of the case steel. I've been using this now for a few months like this but its become apparent that dust is getting in through that hole. The case has filters on the front which would normally stop dust getting in (and which worked well before the mod) so I want to seal up the hole so the filters can do their job again. I assume the idea of cutting a hole in the case base (or side for tower cases) is quite common with modern cooler underside brackets but how have people sealed up the remaining hole to stop dust ingress? I did a search here but couldn't find a similar query - sorry if someone else has already asked this. I was thinking of just taping a bit of plastic bag film over the hole - even though it goes right up to one of the case feet so it couldn't be secured properly there. I'm hoping there might be a better way though. Any thoughts on this please?