This may sound like a total noob question but, when I get my HR-03 for my 8800 Ultra which way do I put the 92mm fan? Blowing onto the card or out from the card

You'll want the fan blowing the air away from the card so it helps dissipate the heat from the heatsink into the surrounding air.

Nick

You'll want the fan blowing into the heatsink. That way the heatsink will stay cooler.

Somehow I don't think falcon26 is going to be happy with this!

Into the heatsink, assuming this means blowing upwards. IMHO it should work better for the overall case airflow.

General rule is: Never go against natural air flow. And hot hair will go up. So make the fan always blow upwards:

Against the HSF if sink is below the card and away from the sink if sink is on top of card.

Agree with fan blowing up so the air moves towards the exhaust, drawing from intake.

All coolers usually have their fan blow towards(in) the heatsink, as this is more efficient for cooling it, but it may not be absolutely required. Thermalright FAQ agrees with fan blowing from bottom to top.

Well it looks like this

http://www.thg.ru/graphic/thermalright_ ... _in_pc.jpg

I have it blowing away from the HSI....but I guess that's wrong right?

alot of aftermarket VGA coolers work on the assumption that the fan will be clowing onto the card, so that the memory and power circuits (VRM) get some cooling. This is usually provided by the stock cooler (particularly on high end cards) and lack of VRM cooling is often the cause of screen artifacts. So blowing onto the card

Also, although it pays to go with natural convection wherever possible, it's usually such a minor factor in component cooling (MikeC's looked into this I believe) that it won't be a huge deal if you go against it.

Or, you could always just try both ways and see which works best!

I used to feel the same way about natural convection (that it was a minor factor in cooling)......that was before I got serious about positive pressure, and totally passive exhaust flow. Take a look at this setup.......



It has absolutely no exhaust fans.....the PSU is fanless. Natural convection and positive pressure vent all the exhaust out through the top edge slots (hard to see) and the fanless Zen. Natural convection is a powerful force in a computer....and ignored too often. Make as much use of it as possible, if you want the quietest possible setup.

Ok I mount the fan with it blowning on the heatsink. I've ran it about an hour now. Here are some results:

Stock Fan

Idle: 68C
Load: 85C


HR-03 with 92mm Nexus Fan

Idle: 54C
Load: 74C

Much better and the fan is only at 1200 rpm's but its dead silent now. I ran 3d mark a few times and it was dead quiet, exactly what I was looking for Now I'm just worried about those memory heatsinks. They were falling off before but I think I got them to stay this time.....I hope

bluefront - I guess an easy way to test that theory is to, if possible, turn the PC upside down with the same access to vents etc. If there's more than degree or two (ie. more than the margin of measurement error) difference, then I'd agree with you. Be interested to hear the results!

Too OT for this thread....this design cannot be flipped. The exhaust would be blocked, and sucked back into the intake. Other setups have proven this theory 100%. Start a new thread on the subject if you're interested....

VRM and mem chip cooling is important too. I've got a case fan for that, so I overlooked the fact.

Your temps may go up during the next month or so as the paste settles and dust starts gathering. Hope you got it right the first time and wish you have a nice everafer with the cooler.

meh, whatever Bluefront. OT or not, you did bring it up. Other set ups have disproven this theory too - stating otherwise makes it sound like dogma, not fact. I'm not saying natural convection doesn't help, but I can't see it being anything more than a minor factor given the tiny heat differentials. As I've said, MikeC's spent time looking into this and, as empiricism proves or disproves theory, simply trying what I suggested (making sure the exhaust vents have a bit of space - easy with a couple of planks of wood) should give a more robust answer. Given that you have active airflow in that case I can't see how any additive effect of natural convection can be anything but inferred.

That way SPCR, and people like the OP, will benefit, surely?

What we all should be doing here at SPCR, is to try to keep our computers as quiet as possible. And that means we need to move heated air out of our cases as quietly as possible. Natural convection is there for the taking.....totally free, and almost silent in computers. If you attempt to force heated air to flow downward, rather than upward, you are wasting energy, and making things more noisy. The problem we face when using natural convection.......the majority of cases are not designed to use natural convection, not to mention heatsinks on cards are below the card in most cases. You have to work at it, to make natural convection work as well as it can.

It's a little more complicated than installing a few ducts......and drilling a few holes.

I don't disagree with you in principle but in degree. The questions I'm interested in are not "does natural convection help?" as I'm sure it does, but "how much of an effect does it have, per se and relative to forced convection" and also "is it enough of an effect to worry about going against natural convection".

I've taken your suggestion and put this up as another thread in the Silent Front. Apologies to the OP for taking the thread off topic!