Question Is single d5 sufficient.

[lingarajug]

Upgrading my system to include 7900x with ek velocity block, watercool mobo vrm block, 2 2080ti's in sli with ek vector blocks (parallel or serial) with 2 360mm and 1 280mm rads and a bunch of 90 degree fittings, will be using asus rog rampage vi apex mobo and swiftech maelstorm 100 d5 pump/res combo, any input appreciated, btw case will be thermaltake core x9.

 

[rubix_1011]

For a loop like that, a DDC is probably a little better suited since it has higher head pressure than a D5. I would get rid of as many 90 degree fittings you can, and assuming this is a soft tubing build and not hardline tubing, this will be to your benefit. If hardline, I would recommend making nice radius bends with a good sweep to avoid tubing collapse.

GPUs in parallel, not serial, if possible - this will help flow restriction.

Dual pumps would also be helpful, or dual loops if you are that close already.

Radiators are some of the lowest-restriction components, so not an issue having 3, although the 2x 360's are way more than you need and the extra 280 is just at the expense of having it.

I would drop the 280 rad and as many extra fittings as you can and simply go with dual DDC or D5 pump loops rather than one big one. CPU/Motherboard block on one, GPUs on the other, each with a 360 and pump+res combo.