GPU & CPU back to back

[acer]

Hi,

I'm currently building a custom build and just want some advice or questions clearing up about back to back gpu & cpu.

How much space do you need between the back of the GPU and the back of the motherboard them? Could they touch? Or be within 1mm or less?

I was thinking of creating a board to hold the motherboard onto and the gpu sit behind it, should I also put a thermal pad on the back of that board for the GPU or would this serve no purpose?

If the GPU was touching or near touching (1mm or less) to a board that the motherboard sat on would this be bad news? (GPU has a back plate)

My case can only really breath from both the sides so gpu and cpu sides and I might be able to fit a couple fans but which is best for a sff, push the hot air out or pull cool air in? If neither really affects temps then which would be quieter?

I know there's a fair few questions in one but if you can help out and answer anything that would be awesome!

Thanks!

 

[tinyitx]

Hi,

I'm currently building a custom build and just want some advice or questions clearing up about back to back gpu & cpu.

How much space do you need between the back of the GPU and the back of the motherboard them? Could they touch? Or be within 1mm or less?

I was thinking of creating a board to hold the motherboard onto and the gpu sit behind it, should I also put a thermal pad on the back of that board for the GPU or would this serve no purpose?

If the GPU was touching or near touching (1mm or less) to a board that the motherboard sat on would this be bad news? (GPU has a back plate)

My case can only really breath from both the sides so gpu and cpu sides and I might be able to fit a couple fans but which is best for a sff, push the hot air out or pull cool air in? If neither really affects temps then which would be quieter?

I know there's a fair few questions in one but if you can help out and answer anything that would be awesome!

Thanks!

Back of motherboard and back of display card touching each other is no good, for electrical reason.

If there is just 1mm space in between them, ventilation is basically nil.
Assuming there is no M.2 SSD installed on the back of the motherboard, this zero ventilation is probably acceptable for the motherboard. Regarding the display card with a backplate, the backplate can be purely for looks but many also act as a heatsink. And, obviously, zero ventilation is not desirable (even though it is unlikely to be critical enough to cause thermal throttle under load or to accelerate component degradation.)

Whether the 2 case fans should be intake or exhaust, it really depends on the design airflow of the case based on the layout of the components.
Both intake or both exhaust or one exhaust one intake? Who knows?

 

[acer]

Back of motherboard and back of display card touching each other is no good, for electrical reason.

If there is just 1mm space in between them, ventilation is basically nil.
Assuming there is no M.2 SSD installed on the back of the motherboard, this zero ventilation is probably acceptable for the motherboard. Regarding the display card with a backplate, the backplate can be purely for looks but many also act as a heatsink. And, obviously, zero ventilation is not desirable (even though it is unlikely to be critical enough to cause thermal throttle under load or to accelerate component degradation.)

Whether the 2 case fans should be intake or exhaust, it really depends on the design airflow of the case based on the layout of the components.
Both intake or both exhaust or one exhaust one intake? Who knows?

Thanks for the reply! I can make more room between them I just wanted to know worse case from someone with experience. I know its kind of a stupid question as the obvious answer would be "as far as possible", but what would you recommend as a good clearance for a back to back system?