Arctic Accelero Extreme III

I've been curious about this for a while - it claims to be better than manufacturer fitted coolers, but has been on the market for donkeys years. GPU coolers ought to have got more competent since then, so how does it match up against something more modern?

This question will have to wait for another day, but till then my 980ti should suffice as a representative 250 W load. My card is a stock clocked EVGA model, and Hexus found the overclocked stablemate to be a capable card (if not quite as good as the best partner cards). My case doesn't have the best GPU airflow, and under heavy load the card will occasionally throttle and get rather too loud for my liking (with typical temperatures of 83 C and fans going at 2300 RPM or so).

https://i.imgur.com/gGTJzmQ.jpg

The arctic cooler is noticeably larger, but not correspondingly heavier - just 628 g for the fans, shroud and cooler; compared to 539 g for the EVGA one. With only 1 more fan and not much more extra mass, could it perform that much different?

Mounting

The arctic cooler comes packed in a neat plastic case that manages to fit all you need (main cooler, small heatsinks for other components, thermal glue, mounting hardware, a ventilated PCI slot cover, and an adapter for running the fans straight off a molex plug) while also being only slightly bigger than the cooler. It supports just about every reasonably high end GPU sold for more than a decade, with AMD support going back to the 3XXX series and Nvidia support going all the way back to the 7XXX cards, however due to the weird connector used by Nvidia on reference RTX cards you'll need to either get the revision 2 of the cooler or grab the adapter from arctic for £2.

Mounting the small heatsinks for the memory and power conversion circuitry is not for the faint hearted - this was legitimately one of the most nerve-wracking things I've done with my PC. Arctic supplies some insulating tape to cover any surface mounted components, but this does not adhere very well and isn't the easiest thing to apply. The glue is also frustrating - it does firm up after enough time, but takes well over an hour to do so. The manual is keen to stress the importance of good surface preparation, but testing to make sure the bond worked requires a lot of waiting around. As my case takes the GPU with the fans pointing up I did the final assembly before the glue had fully cured, as the glue didn't have to fight gravity (and a good hot stress test should help it cure). Knowing which components to cool is an easy part of the process, just have a look at what components got thermal pads fitted from the factory.

Some cards will allow you to keep the stock cooler on the memory and VRMs while fitting the main cooler (unfortunately this card is not one of them), and if you can do this then I'd recommend it - it'll make the whole process a lot simpler. The limit on this tends to be clearance around the GPU (check to see if there's an uninterrupted gap in the square defined by the mounting holes for the main cooler), but also keep an eye out for places where the main cooler heatsink contacts the components on the PCB to help cool them as they may need additional cooling.

https://i.imgur.com/QnnMDhG.jpg
The cooler with the small heatsinks fitted. The main cooler mounting bracket is only test fitted here to ensure clearance.

Mounting the main cooler is fairly simple, albeit more complex than a typical CPU cooler. You'll need to use some supplied double sided sticky tape rings to adhere spacers onto the rear backplate and the main cooler, as well as sticking a foam pad on the PCB behind the GPU. This makes for a very novel mounting system compared to most GPU coolers - the backplate that the cooler is mounted to typically goes around the components behind the GPU, meaning the PCB is being loaded in bending to squeeze the GPU onto the cooler. On the arctic cooler the foam pad is compressed by the backplate used by the accelero III, such that all the mounting pressure is being applied directly behind the GPU - under very high loads (i.e. if someone overtorques the fasteners) the bending moment could bring the middle of the GPU die away from the cooler, but the arctic cooler is immune to this.

You'll also need to plug in the supplied fans, which comes with a mini sized 4 pin PWM connector. It surprised me, but turns out GPU manufacturers tend to stick to the same pinout as case fan PWM connectors (just with a smaller socket). The arctic fans work just fine with the fan control on my board, although they don't stop spinning at 0% PWM. My old card was semi-passive, but as the fans keep spinning the arctic cooler makes it active all the time. This keeps them at ~600 RPM all the time, but they're really quiet (as you'd expect for 92mm spinners) so the noise produced is quieter than the rest of the stuff in my case.

The final assembly is 3 slots thick, as you'd expect. This is partly due to the wide compatibility - there's a ~1cm gap between the bottom of the cooler and the PCB to accommodate any components, whereas a factory fitted cooler is designed around the exact components used so makes better use of the space. This gap should give a nice big area for air to flow into though, making it easier for hot air to get out from the fins (on a normal cooler the air can only get out by passing the whole length of the fin).

https://i.imgur.com/CwQucs6.jpg
and done. This took 2 hours, the vast majority of which was spent waiting for the glue to cure.

Performance

In one word, staggering.

Highest values seen in Firestrike extreme stress test (room temp of 22 C, intake fan at 850 RPM):

	EVGA ACX2.0	Accelero III
Stability, %	96	97.9
Peak GPU temp, C	84	70
Fan speed, RPM	2370	1383

This cooler performs well above stock, while also keeping fan noise down substantially! It's so quiet I've even adjusted down the fan curve for my intake fan - while before it was drowned out by the GPU cooler, now it became the loudest thing in the system. With all the headroom I even tried an overclock, and the card is still substantially cooler&quieter than before while now running 200 MHz faster on the core and 350 MHz faster on the VRAM with a 10% higher TDP (previous boost speed under load was 1.2 GHz, and with the extra power the GPU peaks around 75 C). This resulted in a 13% improvement in 3dmark results (going from an overall score of 5610 to 6388 in time spy), so I'm pleased.

Other than the extra fan, there's no obvious reason why it works so well - it's about the same mass as the old one, there's the same number of heat pipes, and with the open space under the cooler the fin volume is probably comparable. It could be down to the fan, or better airflow due to being spaced away from the card, or it could be that arctic's engineers are just better than EVGA's. Either way, it's a big improvement.

In conclusion, I'd recommend this cooler to anyone who enjoys tinkering with their PC. ~£50 for a ~10% performance improvement (assuming modern GPUs have similar overclocking headroom) is steep on an older card like mine, but with current GPU prices this makes financial sense on a 2070 or better GPU before you account for the quieter operation.

Secondary benefit: you end up with spare heatsinks and thermal adhesive
https://i.imgur.com/nsGKnWv.jpg