Basic case cooling question

[Humboldt]

My 24/7 folding rig has 2 cards running with no case fan.

When it was just a single card (GTX 460) it wasn't a problem, it's got great cooling with its fan and heatsinks. I just left a case panel off and cleaned it often.

With a second card (8800 GT) the heat built up quickly and the cards shut down.

Solved cracker-style with a table fan blowing directly into the still open case from 2' away.
Right now the cards are at 54 C and 64 C.

Found a Zalman 80mm case fan in a parts box.

Wondering what the pros or cons would be of installing the case fan and closing the case up, compared to having the case open and using the table fan.
I know the dust and the power consumption would both be less with the case fan so that's what I'm leaning towards.

Thanks.

[YeOldeStonecat]

Pros of putting in an adequate chassis exhaust fan.....better aesthetics, less noise, less power consumption.
Cons...will require a little bit of your time to set it up.

Pros of using existing McGuyver method of table top fan blowing adjacently into the open chassis...it's done and working, zero further investment of your time and effort.
Cons...using up more of your table top space, more noise, , an extra dollar or three on your monthly electric bill, ghetto looks.

[Mark]

run the case closed with proper fan setup

PM me if ya need some fans, i have a ton of extras, let me know what size ya need

[Rivas]

Try open case. They have huge fan on top, fan for hdd's and you can even place regular fan close to it, it's open no screws required. Aerocool strike-X is around 100 bucks. Fits most MB's. For removing the dust use some small vacuum, works like charm.