Is ther a problem with top mounted rads?

I've got this shiny new case and I don't really want to cut the crap out of the front to fit in two 120mm's and my rad. It will all fit nicely mounted horizontally in the top, is there a problem with this setup? It's just that I havn't seen many people do this.

The only problem, is it can be a bear to get all the trapped air out of it. That air can cause flow restrictions and even cause some of the coolant channels to not be used.

BUT, if everything's bolted down in the case, it's no problem tipping it (assuming leak proof reservior/no reservior) and giving it a good knock to bust 'em loose. Just like knocking on a door, no need to dent the case

I think I can live with bumping my case a few times, thanks for the nfo.

BTW - I just got my first star; I'm so proud!

I would atleast make a covering that is spaced above the radiator so nothing can get spilled into the computer. I have known a few people that have done blow holes~ rads on top and som crazy person at a lan or there kid puts a drink ontop and it tips over and uh well.....not good to have mountain dew inside your computer

For looks as well as practicality i was thinking of some nice external duct, alu/plexi maybe.

I just put a fan grill on mine. Havent had any probs.

My D-Tek heater core is mounted just like you said... top of the case horizontally, with a blowhole directly above it... I squeezed it into my top two 5.25 bays. Haven't had a single problem.

The only thing I don't like is that if I want to use one of those bays, I'm outta luck. It's the only place I can fit it though in my case, even though I have a Lian-Li pc-60 which is fairly roomy. Will NOT fit down in the lower front of the case.

Btw I suppose depending on your config, it could be a 'bear' to bleed your system. As long as it's securely mounted though it won't be a problem. Mine isn't bolted, but it sits completely tight between the walls of the case. So I just shake the case from side to side when I need to bleed it.

mounting it in a blow hole setup won't give you steller proformance, b/c its going to be sucking hot air out of your case. Unless your water colling everything, it won't be a problem.

Thanks for all the info. It is not actually going to be a blow hole, more like a suck hole; two fans blow the air down through the rad and underneath is a duct and another fan sucking air out the back of the case(above the PSU). I know there will be less air flow inside the case but there is also an 80mm(HDD) and 120mm intake at the front, and a 92mm outlet plus the Antec dual fan PSU as another outlet - so hopefully enough air flow. Still debating whether or not to put in a GPU waterblock.