I had access to both the U12S and U12A for testing. I could not find information on the actual heatsink difference between the two in terms of performance and wanted to test it.

CPU: 5950X (C.O -25)

MOBO: Asus Strix B550A (Fmax Enhancer OFF)

Ram: 32GB 3200mhz Cl16

GPU: RTX 3080 FE

Room Ambient Temp 21C

Test used Prime 95.

Test to See Heatsink Difference - Fans at max speed.

U12S Heatsink w/ 2x NF-A12x25s 76C

U12A Heatsink w/ 2x NF-A12x25s 74.6C

Noise Normalized Test 40dba

U12S Heatsink w/ 2x NF-A12x25s 85.2C (1498rpm)

U12A Heatsink w/ 2x NF-A12x25s 84.1C (1490rpm)

TL;DR

Depending on pricing, NH-U12S with 2 NF-A12x25 is the same price as NH-U12A and maybe a better value (at least it is in Canada) since you get a free NH-F12, NH-U12A heatsink marginally better than NH-U12S with at most 2C diff.

Edit: I also tested the heatsinks with NF-F12, no difference was found less than 0.5C diff and can be attributed to run to run variation.

im planning to buy an nh u12s + fan kit due its cheaper but u12a have another difference? (i have a ryzen 7 5700x)

Is it worth getting the u12a when it comes at a $40 price premium (and doesn’t have chromax covers)? From looking at the reviews, it looks like they only differ by 1 or 2 C, and I assume I could just put another fan on the u12s for a push/pull configuration. I currently have a Ryzen 1600, but plan to upgrade to the 3000 series at some point, and want to know if the U12s will be sufficient in the long run, or if it would be better to splurge on the U12a.

I have an 8700k and it performs great when gaming but holds me back a bit when video editing. It’s currently at 4.3ghz and it can be clocked to 5ghz but thermal throttles after about a minute. I am currently using a cryptic h7. Most people who are running at 5ghz are using coolers like the dark rock pro 4 and the d15. I am using an itx case and I don’t have the space for these coolers. I don’t want to go the aio route since they are pricey. The biggest coolers I can fit in my case are the u12a with single fan or the u12s with dual fan. Which one would give better cooling performance?

So I’m thinking of getting a new PC soon and I’ve heard a lotta good things about Noctua. Did some research and decided on either of these 2 products(cuz of clearance issues with Ram and all that). I will be pairing this cooler with a R7 5800x which is known for thermal issues, so I’m wondering is it worth the extra $30 (more like 40-70 in some places) to get the 12A over the 12S. Pc will be used mostly for gaming with occasional AAA titles like Shadow of the TR and Halo infinite.

Edit: Upon reading the comments and reconsidering my choices I have decided to get the NHD15 lol

Running a STRIX x570e with a ryzen 9 3900x, g.skill Trident Z neo 16gb x 4 CL16-16-16-36, 1tb Sabrent Rocket pcie4.0, Seasonic Focus GX-850 ina Cooler Master HAF XB EVO. (Waiting for AMD to realease their GPUs to pick among the Newest gen)

Assuming a second fan is connected to the NH-U12S, is this same performance as the NH-U12A? I recently got a NH-U12S Chromax Linus Tech Tips for what i thought was a good price. However seeing how I have to buy a second fan, im wondering if is should just skip the aesthetics now and go with the NH-U12A. Why doesnt the NH-U12S come with a second fan to complete the Push Pull configuration? Im finding them sparingly on ebay for $27 While there $35+ on Newegg. Does anyone know where I can find a Noctua NF-A12 x 25 PWM 120mm Chromax fan for sub $25?