FEATURE As the next generation of M.2 SSDs have made their way to consumer platforms, we’ve seen some outlandish cooling solutions attached to them: heat pipes, 20,000 rpm fans, and even small liquid coolers.
Adata Project NeonStorm is maybe the most extreme example we’ve seen thus far. It adds a self-contained liquid-cooling system to the gum-stick-sized drive, replete with a pump, reservoir, radiator, and a pair of fans. It is, however, far from the only one. Fans and even entire cooling towers have been mounted to TeamGroup and Inland SSDs.
But are PCIe 5.0 SSDs so hot that active cooling is required, or are all these fan-less SSDs a gimmick preying on gamers’ ignorance or irrational love of unicorn barf? Did we mention that many have RGB?
Adata claims in a blog post with few specifics that typical passive heat dissipation is unable to fulfill the demands of PCIe 5.0 SSDs and that some form of active heat dissipation is now required.
Jon Tanguy, who works on SSDs for Micron’s Crucial product group, is skeptical. He tells The Register that, while the latest generation of SSDs is running hotter, Crucial doesn’t see the need for active cooling for their drives just yet.
Faster NAND is hotter NAND: The bandwidth per lane typically doubles with each subsequent PCIe iteration. We were getting close to the theoretical maximum of 8GBps with PCIe 4.0 SSDs. After accounting for bottlenecks and storage overheads, a PCIe Gen 5.0 x4 SSD can now achieve somewhere between 10 and 14GBps.
The level of activity on the M.2 form factor means greater temperatures not only for the storage controller but also for the NAND flash itself.
Tanguy demonstrates that NAND is most happy within a rather small temperature range. “NAND flash actually likes to be ‘hot’ in that 60° to 70° [celestial] range in order to program a cell because those electrons can move a little bit easier when it’s that hot,” he stated.
However, if the temperature rises above 80°C, problems arise. At certain temperatures, the SSD’s built-in safety features may forcefully shut down the machine to prevent damage. However, before this happens, users should expect to observe a drop in disk speed while the SSD’s controller throttles itself to prevent data loss.
This is one of the reasons why, even during the PCIe 4.0 generation, aluminum or even copper heatsinks were available alongside luxury machines.
The upshot is that to get peak performance with PCIe 5.0 SSDs, particularly performance-oriented versions, some kind of cooler is required. The question of whether it has to be actively cooled is altogether different.
Crucial’s upcoming T700 SSD, for example, will come standard with a passive heat sink. The manufacturer will sell you a version without the heat sink if you wish to use your motherboard’s built-in heatsink or a third-party one. Tanguy highlights the need for a cooler.
Tanguy and his team believe that active cooling is unnecessary with this generation of SSDs as long as there is adequate airflow over the drive.
“We decided that adding active cooling was probably more than our customers would want to do,” he explained.
Tanguy believes this to be a particularly difficult problem to tackle once PCIe 5.0 SSDs make their way into the notebook category, where airflow choices are restricted.
More points of failure, and worse capability: The good news is that attaching a fan or liquid cooler to an SSD is unlikely to harm anything other than your pocketbook. “I don’t want to sit here and say that all of these things won’t work because they most likely will,” Tanguy said of actively cooled SSDs.
While NAND flash prefers higher temperatures, Tanguy says there’s nothing wrong with running it at lower temps.
In the view of this humble vulture, attaching active cooling to an SSD is akin to utilizing a gigantic dual-tower cooler or 360mm radiator to cool an Intel Celeron. It won’t injure anything, but it won’t make much of a difference in terms of performance, and it’ll cost you far more than a more adequately sized cooler.
Remember that at peak loads, these SSDs are only using 11.5 watts, and due of the M.2 form factor, maintaining a sustained load is difficult. Most consumer SSDs have transfer rates indicated for relatively bursty applications. Transfer rates generally fall to a fraction of what is stated after the SSD’s DRAM and/or SLC caches are full.
As a result, the drive is unlikely to function at maximum load for a lengthy period of time.
However, just because active coolers aren’t harmful doesn’t mean they can’t cause issues with dependability or compatibility. Tanguy claims that every moving part added to a storage system introduces another potential source of failure.
“We spent a lot of years taking moving parts out of the storage systems to get to this point now where we’re putting moving parts back in, just to make it more likely to fail or become noisy,” he explained.
Consider the ruckus a 20,000 rpm fan might produce when its bearing fails after a few years.
Then there’s the issue of compatibility. Today, many motherboards include integrated heat sinks for M.2 SSDs. Using something like Adata’s Project NeonStorm liquid-cooled SSD will almost certainly mean foregoing that.
These SSDs’ larger coolers may also interact with other components, such as CPU tower coolers or GPUs. This is due to the fact that the majority of PCIe 5.0 slots are positioned directly beneath the CPU socket to decrease trace length and assure signal integrity.
So, do you truly require a liquid-cooled SSD? We doubt it, but if you insist, we can’t say we blame you.
