Discussion Surprising results with 645LT as a janky U9S

Diamorif

Cable-Tie Ninja
Original poster
Jun 9, 2020
211
105
https://preview.redd.it/9lg9s8g4itn...bp&s=ece8317c50ffb8f841fb965699e3dbb289c3e084

So I was initially going to post this as a bit of a joke showing off my janky 645LT doing its best U9S impression, but it has actually produced some really good results, and wanted to see if anyone has had a similar experience.

I was initially trying to find a stopgap for my C26 build that had a 240mm aio bottom-mounted under my 6800XT. While the max temps on the 5800X with the 240 were a little better than the current set up (maxed at around 70C v 75C currently in a stress test), the exhaust from the rad was making the GPU climb above 80C and was a bit worrying. I replaced the AIO with the 92mm version with two NF A9s set to exhaust (intake performed worse than both and made a bunch of turbulence noise) and have been getting idle temps in the high 20s and in-game temps in the low 60s.

I'm really taken aback on how well the tiny guy compares to the 240, like a few degrees worse under load and a solid 10c lower at idle. I was going to get a silver arrow 130, but I may just end up sticking with his little gem. Curious if anyone else has tried this in an Ncase or something and if the results were at all similar.
 

elvendawn

Average Stuffer
Nov 12, 2020
60
27
Yeah my 645LT with just a single NF-A9 is better than my NH-C14S with NF-A12 and NF-A12x15, and more quiet under max load, been very happy with it.
 

Diamorif

Cable-Tie Ninja
Original poster
Jun 9, 2020
211
105
I was very surprised, glad I'm not going crazy. I'm mostly fascinates that it keeps pace with a 240. never expected that.
 

Diamorif

Cable-Tie Ninja
Original poster
Jun 9, 2020
211
105
Fine? It sits on the other side of the room from me but I did the normal set it to 60-80% in bios? Kinda confused by the question.
 

Diamorif

Cable-Tie Ninja
Original poster
Jun 9, 2020
211
105
not an issue to my ear, but that's a pretty subjective thing. even at 100 percent, it is barely perceivable with my ear up against the case with the fans going. the 645 has some sound dampening in the pump head as well from what I've read.
 

elvendawn

Average Stuffer
Nov 12, 2020
60
27
Hi @daddelbud,

My computer is silent while idle and barely audible with heavy gaming. Mostly due to the 2x NF-A12s cooling GPU ramping up from 40-80% speed. I leave the pump at minimum rpm (40% which isn't audible) and just set the NF-A9 on the radiator to ramp up from 40-80% which is still very quiet at load. Most games keep the CPU at 55-60c which is around 50-60% fan speed.


However, even with the advancements in the gen6 pump and extra sound dampening in the housing, the pump is definitely audible at max rpm, which is like a faint groaning - subjectively not a pleasing sound like NF-A12s deeper hum at high speeds.

Idle


Valheim - okay not the most heavy game, but a fine example
 

elvendawn

Average Stuffer
Nov 12, 2020
60
27
NCASE M1
Strix B550
5600X
2080 Deshrouded (can't get a freaking 3080 or 3070 even after all the Newegg shuffles, and Best Buy drops :confused:)
3x NF-A12x25's (two exhaust on the GPU, one intake on the side rail in the center to keep moving air on the MB)
I want to figure out a 3D printed bracket for a top fan and put a tinted TG side panel on it.
645LT with 1x NF-A9x25 (exhaust)