Which is best Radiator for GPU Cooling?

the 280 is the best. think in terms of surface area when it comes to radiators. a 280 is a bit overkill just for a gpu though, and you could easily get away with a 140mm or a 240 mm and still get great temps at a lower price. rule of thumb is a minimum of 1 120mm rad per component for water cooling (so a 240 could cool 2 gpu effectively enough)

well first off you need a specialized block for that gpu, so i hope you have that figured (there are two gpu chips on that board). the bigger the radiator the better, so which do you think would be better based off this information and the radiators you have listed. not to be cheeky but use a little bit of cognitive power.

Correct, but i above stated that the larget the surface area of the radiator, the greater the cooling will be. you only have one 280mm option while the rest are 240. by logic the 280 is the best. it may take up more space, but it has the greatest surface area for cooling.

Sorry I hope im not catching this forum a little to late.

But there is a point to be made about more surface area equals more area to cool the liquid. But you also need to factor in 3 other very important concepts. Though yes a 280mm is larger than the 240mm by those 2 dimensions, but the 3rd dimension is also just as important. That is, the 'thickness' of the radiator. If you have two 240 mm radiators and 1 280mm radiator, lets say one 240mm is 20mm thick, one 240mm is 40mm thick, and the 280mm is 20mm thick. That would actually increase the surface area of the 240mm with 40mm thickness to be far greater than the 280mm.

Another important factor, is fin size/depth. Some radiator fins are very tight which require the use of more powerful and faster fans. Some radiator fins are spaced farther apart, those cool less but only require 'quieter' and slower running fans.

The third factor, which ties right into the second, is fans. A 240mm uses the more standard 120mm fans. There you have an extreme amount of options for fans by almost every manufactur. You will have your high speed performance, and your low speed quiet. A 280mm uses the less standard 140mm fans. Now in this day of age there are quite a bit of options for high performace or quiet 140mm fans, but this is something you do need to take into account. Since when you buy a radiator, even if it includes fans, you will need to buy the specific needed fans for that radiator. If your radiator comes with fans, odds are theyre crap, loud, and don't move a good amount of air. So that's something to remember.

But also realize, that a 280mm radiator is quite a bit larger than the 240mm. Not just 40mm. And even if a radiator is 240mm or 280mm, that's just fan area specs. The radiator itself still needs the 'housing' that holds those fins, and still needs connections to put the fittings onto.
Perfect example of this, is that my case allows for up to a 360mm radiator in front and/or up to a 280mm on top. Now, what they should've noted is that not all 240/280m rads run the same size. I have well had a xspc 360mm and a xspc 280mm radiator, and they wouldn't fit. The corner they share, well they cant share it, they both need it. So luckily I could return mine, and get a 240mm to run with my 360mm. Not that this is your case, just thought id share my story.

Identical cooling area size, unless you consider 1 inch extra on the 240mm to be a huge amount



Now, with all that being said, I just looked into your 3 radiator options/your original question as to which is better.

The ek 280mm - is 317x145x '55mm' (55mm thick), stated fin are 10FPI - designed for ultra silent low airflow fans

The ek XTX 240mm - is 280x130x '64mm' (64mm thick), stated fins are 11FPI - designed for both high and low speed fans.

The ek XT 240mm - is 276x123x '47mm' (47mm thick), stated fins are 11 FPI - meant for low speed fans
FPI = Fins Per Inch (more fins more cooling, also need higher powered fan to force air through tighter space)

So my take of the matter, the ek xt might as well scratch that one off. Its smaller in every area, and uses the same fins as the other 240mm. The 240mm xtx is a higher quality, 10mm thicker which isn't really that much but will allow for powerful 120mm fans, and offers 1 more fin per inch. The 280mm has a larger surface area, but is thinner and offers less fins.

Now technical, actual cooling area (there are 25.4mm per inch) *this is 3d total cooling size
280mm - 15,400mm/22in
240mm - 15,360mm/23in
So as you can see, there is really next to nothing as far as a difference in actual cooling area. But the added depth of the 240 offers a longer amount of time air will be passing through the radiator, as well as more surface area itself, and lastly offers more fins per inch. So not only does the xtx 240mm offer more surface area by adding its 2 dimension by its axtual 3rd dimension, but add in it offers 1 more fin per inch, so 23 more fins for water to flow through and contact the air in which is passing through.

So, identical cooling area size, unless you consider 1 inch to be a huge amount.

Now, make sure your case fits them both first of all.

But my personal preference would be get the 240 xtx, its a far superior quality radiator, which lets you use either fast and powerful or slow and quite fans. With that as an option, id get 2 great 120mm pvm fans. PVM fans are variable speed fans, set them up with your fan control software and they can be quiet when your not taxing your cpu, but once you start they speed up and cool great. Best of both worlds. Noctura and Coorsair make great 120mm high performance pvm fans, id recommend either of them. They'll run you about $25 a piece or $50 total, but they use high quality bearings which are rated for a great life expentency, offer exceptional performance, and will do what you need them to do.

Hope this helps.