I want to have a i5 4670k and two 780s
how much rad space and
what is a case that can fit them comfortably
Questions.
How many rads are you planing on having (water cooling CPU only or CPU+GPUs) ?
Do you have a specific budget for the rads or case ?
Have you considered getting a closed loop cooler for the CPU and NZXT G10 + closed loop coolers for the GPUs ?
the number of rads doesn't matter as long as they fit in the case
i will be cooling both CPU+GPUS
No particular budget but i don't want to spend more than needed
and i have considered the closed loops but they are not aesthetically pleasing to me
Rule of thumb is 120mm per component, and 120mm for each overclocked part. So with overclocking, you would need 720mm of radiator space. That's three 240mm radiators.
You could get away with less. There's a lot to take into account.
Personally, I would grab an i5 4670k and a single 780ti and watercool those. Dual GPU configurations can be problematic. Requiring more power, and they don't always work in specific games.
to give you an idea I have an i7 920 and a gtx 780 water cooled using one 360mm (60mm thick) rad both overclocked. gpu doesnt go above 46 Celsius even on stress tests, my cpu at 3.8ghz when at 100% will be around 60 Celcius. the fans on the rad are also on very low. If i had another GPU might go and add an additional 240mm rad.
I have a corsair 750d the 360 in the roof was fine, the 60mm thickness was a squeeze with my mobo though but it worked. there is also room in the floor or the front for that additional 240mm rad.
hope it helps
If you have a standard size of board and card, then you might consider the NZXT H440 and one of those Alphacool Monsta 360mm radiators in the front of the case would be really cool. If you are concerned that this will still not be enough cooling, then you can actually still fit in another 240mm radiator in the top. I like Alphacool for radiators because of their copper and brass construction. I like EK for their water blocks, but that is almost entirely because of aesthetics. For reservoirs, get what you can afford and hide it if you can't afford a particularly attractive one. I would recommend trying to plumb your loop with hard acrylic tubing instead of flexible tubing. The flexible tubing leaches plasticizers into the coolant and degrades your radiators and pumps over time.