its probably easier to cool a big hot chip than to cool 1000 small chips because the heat is localised and creates a perfect use case of a big heatsink/fan or an off the shelf water cooling solution similar to what millions of PCs have in them.
Actually the opposite. Cointerra's 500 Gh/s will need a big fancy heatsink or water cooling system. But look at Bitfury's 400Gh/s rig with 256 small chips. They need neither heatsinks, nor fans, because the heat is so well distributed that air convection alone does the job.
i think BitFury's chip is awesome, dont get me wrong. im very impressed by what he's done. its a phenomenal achievement.. even more so when you hear this is effectively his first asic! the guy's a genius!
but i think youre talking chalk and cheese. the bitfury boards that are operating without heatsinks and fans are in open air and are very hobbyist looking things - they can only rely on convection when theyre on someone's desk in an air conditioned room. When you put them in a box, and make them legal to own and sell, id be shocked if they didnt need fans for their airflow.
Theres no magic here. BitFury's 400 GH set of boards consumes 400 Watts. Youve got to move that heat out of it, somehow. it cant be done by convection without either heatsinks or fans once its in a box. And its not likely it will stay unboxed when its sold for more serious use.
But these are two different strategies to achieve the same end goal. there's nothing wrong with either strategy as long as you can hit the price and the power consumption targets.
1. The Ant colony approach. Lots of tiny low power chips combining their strength in numbers to achieve a goal. These guys are best demonstrated by BitFury but its the same strategy employed by Avalon, AsicMiner, CoinLab/Alydian, LabCoin, XCrowd etc. BitFury's is by far the best in class in this ant colony model.
2. The 'big hot chip' approach.. like KnC, Hashfast, Cointerra (and to a lesser extent, presumably AMC/VMC and the rest of the 28nm crowd). These guys need large heatsinks and/or water cooling... because the chips are designed to be run at their maximum thermal capacity (250-320 watts, according to the specs of the cooler knc are using). but the good thing about focussing all the power into small concentrated spots is that your heat is localised and you know where its coming from and you can employ heatpipes or liquid to extract the heat directly from the chip to the outside of the box. you dont even need much airflow inside the box as all the heat leaves the box much more efficiently. heat transfers more efficiently in liquid than it does in air.
the question of price and performance will rear its ugly head.
ignoring what bitfury, knc, hashfast and cointerra are actually charging for their products right now. What do we think they will cost, per GH?
do we think that 256 low power (bitfury style) chips, packaged in their QFP48's is cheaper than the equivalent hash power using KnC, Hashfast or Cointerra's single but very much bigger die presumably packaged in an intel style ceramic packaging? clearly the latter is MUCH more expensive than the former, in terms of a single unit. but the former needs 256 of them to hit the same perf target that the latter hits with one expensive chip and expensive package and expensive cooler. So which one will be cheaper to produce in the long term? (i suspect the big hot chips with all the baggage that goes with them, will ultimately be cheaper and lower power than the large quantity of smaller lower power chips that you will need to hit the same performance target).
but its a very interesting exercise and i cant wait to see how they all fair. and of course, all of them will be working on their mark-2 chips utilising what theyve learned from their mark-1 chips so the next round will be even more interesting!
-- Jez