Building a computer questions

So I haven't built a new computer in years but plan to and have the following questions.

Is it recommended to place the heat sink/coolant on CPU before or after installing mobo in the case?

Is it recommended to install the radiator and 2 fans (h100i) before or after mobo placed in case?

I read "pull" exhaust is better than "push" for the fans from the h100i cooler. Any comments on that?

Thanks!

Is it recommended to place the heat sink/coolant on CPU before or after installing mobo in the case?

Well, most aftermarket heatsinks have backplates; depending on your case, you may have no other choice. If there's no cutout in the motherboard tray to let you access the backplate area, you'll have to preinstall it. (That's usually easiest anyway.)

Is it recommended to install the radiator and 2 fans (h100i) before or after mobo placed in case?

That would be much easier, I think, after the board is in, and screwed down. You might be able to do it ahead of time, but it would be awkward, and you'd be likely to twist your hoses.

I read "pull" exhaust is better than "push" for the fans from the h100i cooler. Any comments on that?

Well, you normally want to be exhausting air out of the case through the air cooler, and setting up a pull when the cooler is flush against the case would require an external fan. No idea on relative efficiency, but the cooler itself is designed for having the airflow be pushed from the inside of the case, through it to the outside.

Going in reverse might drop your CPU temp a degree or two (since you're now pulling the coldest available air in over the radiator), but then you have to figure out where your air is going to exhaust. Going out the front is usually bad; if your case has air filters, they'll usually be on the front, and they'll only work if you're pulling air in through them, not pushing air out.

An overall airflow of front to back is probably going to be best.

It is a fractal R4 case and the fans and radiator would be on top of the case.

I use my own custom watercooling built from Danger Den (RIP). I've been doing it for about 10 years.

I install my blocks before putting the mobo in the case, and install the tubes, rads, and pump afterwards (once in the case). This is because the blocks I use use nuts to attach to the back of the board and it would be impossible to do it otherwise. I also align the rads where I want and cut the hoses to match the distance once I am sure where everything will go.

The book from the Mobo manufacturer will also tell you to install the factory CPU fan before putting the mobo in the case (if push lever fastener). Just be careful of static electricity. Make sure you are grounded and push against the pad the mobo ships with.

In terms of Push vs Pull... I use SilenX 120mm fans on a triple 120.3 Thermochill Radiator. The reason Pull is better than Push (pull air away from rad rather than push air through it), is because Pull is more evenly distributed. Think about it... If you blow on a pipe, you are only really cooling the spot you are blowing on. If you pull air from all around the pipe, you are cooling evenly all around it.

The studies suggest not huge differences between the two and a push/pull combo is one of the best. Set one fan pushing and another pulling on the opposite side, but it's not really necessary if you're cooling a newer smaller die cast processor. They run pretty cool already.

I am also assuming that you are using a closed loop cooler instead of filling and cutting the hoses yourself. If it's a push fastener, I would probably install the board first to get an idea of how I am going to mount the rad, then push on the block. I do recommend the instructions they send you over anything to keep warranty though.

I install the fans before installing the rad. You need to know the exact size you're working with to mount it.

I top mount my rads, but run a T-Line above them for bleeding air bubbles. Air always goes to the highest spot in a loop, so the fill tube should be the tallest point. I don't think you have to bleed and fill that system though.

This is what it should look like:
IMAGE(http://www.overclock.net/content/type/61/id/1281153/width/350/height/700/flags/LL)

I used to make my own computer cases out of wood, but swapped over to using server cases for the extra space. I made an R2-D2 complete with dome, but it wasn't as efficient as an old server case I salvaged from the office when they upgraded.