Removing the covers.

[akif]

Isn't it a cool idea to remove the chassis covers for best cooling of the interior?

[Abbadon]

initialy I would agree, it will keep the case cooler.

but

removing the covers lets a lot of dust in, dust will clog up your heat sinks and reduce their effectiveness. It will also clog up the fans which increases noise and decreases effectiveness & lifespan.

Dust will enter your case wether the cover is on or of, but with the cover of, it'll be much, much worse. Besides, the case is there for a reason: to protect some pretty fragile technology. I sure wouldn't feel comfortable with it beeing of all the time :)

on sumer lan-parties, when temps go way up and my systems runs heavy games for long periods of time I will occasionaly take the covers of, but that's like 10 days in a year tops.

[Whyzman]

I would say Abbadon is "right on" in his assessment! ;)

If your fans are placed properly and are of sufficient CFM (cubic feet per minute) your rig should keep cool and clean...

I use an AC filter on the front fan which I monitor regularly and clean or replace as necessary. Canned air also works well to make sure fins and such are dust bunny free!

[Budfred]

And many systems actually run cooler with the cover on, if the air flow is set up to maximum potential.