Log Velka 3 psu placement - TOP or BOTTOM?

nightshift

Airflow Optimizer
Original poster
Jul 23, 2020
268
168
I was contemplating on a Velka 3 build since about 6 months now but was terrified of using a loud flex-atx psu. Yet I recently noticed that densty.sk is bringing the Enhance VK edition psu's to Europe as well - meaning that I'm really out of excuses to not move my mini ITX setup from my beloved Dan A4 to the Velka 3. I'm very satisfied with how my configuration runs in the Dan A4 and definitely intend to return to it once I can justify the purchase of a full-sized gpu more powerful than my dear Gigabyte 2060 ITX. Until then since it qualifies regarding dimensions, the Velka 3 seems like an ideal home for it.
However, I direly need the advice from good people of this forum who worked with this case (2.0), before I attempt to make the assembly:

In what orientation should I build within this case? Should the psu be below, or at the top?


This has to be decided before even installing the cooler on the mobo as I would like the heatpipes of the L9a to be oriented correctly - so pointing up. There are pros and cons for each scenario.
  • With the psu BELOW, it might be a bit difficult for it to draw air in from the bottom, but since my setup is a 3300x paired with a 2060, my build is not all that power hungry. Yet warm air can freely exit the case on top, but possible heat of the psu can heat up the mobo and gpu from below. I remember the Dan A4 being hot at the top area where the warm air leaves the case above the mobo while gaming. There are quality of life reasons too: the wifi antennas would not interfere with the usb ports on the mobo, the heavy psu at the bottom would grant more stability and I would be able to use super convenient 90 degree power cords like this due to their orientation.
  • Now when the psu is on TOP, it has nice access to fresh air. Yet this might be negated as the gpu and mobo might warm up the psu from below. Can the air exit through the tall side panels too? M.2 can also produce heat, right below the cpu cooler. With the riser connecting to the gpu from above, it's heatpipes are now also pointing upwards - possibly resulting in ssslightly better temps (this I don't know for sure). But basically that's about it. However according to the manual, this is the intended way. And it has to be a reason for this, can someone enlighten me?
Is there someone who tested both with the 2.0? What would be the best long-term option here?
 
Last edited:

Overtek

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OVERTEK
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May 22, 2017
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www.overtek.co.uk
I cannot comment on the case.

However from the PSU side if things it would be better if that can draw cooler air in from outside the case and exhaust.

With some exhausting for the rest the system.

By long term though, that depends what you mean. You simply can't have your cake and eat it, the quieter the fan and higher the load the higher the internal psu thermals will be. ENP-7660B does have a massive temp capacity in that sense. But if I was to deploy this PSU in a server based application in a warm rack for max life I'd probably be bypassing the current fan thermal/load voltage map and be putting in a ARX fan with ceramic sleeve and ceramic shaft running fixed @ 12vdc. Noisy yes, but a fan that can provide 500,000 hour mtbf, all be it thats based on at 25 degree C and below ambients, that fan would probably out last the other components, but it would also help to max life all the other components like the 105 degreeC rated primary Rubycon cap.

How long do you want it to last? is it be used 24/7, maybe crypto mining in the background etc etc. Or just a bit of day to day usage?

PS if you want this PSU with loom customisation, more than happy to chop and recrimp etc. Just an everyday job for us and the 1.5 Ton crimp machine ensures a good crimp every time, even still somehow have all my fingers lol.
 

nightshift

Airflow Optimizer
Original poster
Jul 23, 2020
268
168
Thanks for the reply. I will only use this build as a mobile and compact daily driver for my everyday computing needs - no server applications or crypto, just internet and occasional gaming. A complete 2020 build, full pcie 3.0 - RTX 2060 ITX gpu with a Ryzen 3300x on a Asus b450-i mobo. RAM is pretty good though Ryzen optimized CMK16GX4M2Z3600C14 from Corsair. Regular low profile sticks that are on the Matisse compatibility list of this board, so might as well.
The question was more about which orientation is better for the components to keep cool and the air to exit. This is a very well ventilated case and I suspect that the gpu+mobo can heat up the area above, so I think I'll be placing the psu underneath them and find a way to elevate the case with higher feet somehow.