SK hynix Platinum P51 2TB PCIe, Starring The Alistar Controller

The House Always Has An Advantage

Home-cooked NAND And Controller

SK hynix sent over the evolution of the Platinum P41 PCIe 4.0 NVMe drive, a PCIe 5.0 drive with the expected moniker.   The P41 sported their in-house designed Aries ACNS075 controller and 176-layer 3D TLC, while the Platinum P51 has the new Alistar Gen5 ACNT093 controller and the flash is now 238-layer 3D TLC.  There is no active cooling with the drive, which isn’t required considering the lack of any thermal throttling during testing, nor is there a proprietary heatsink you need to remove to install it in a motherboard which already has heatsinks for M.2 drives; generally all the new models currently on the market.

This look at SK hynix’s Platinum P51 features more pictures than it does SSDs, as I lack the stable of storage that some possess.  Instead it is up against the P41, an unfair competition with it’s PCIe 4.0 x4 interface and another PCIe 5.0 x4 drive from TeamGroup called the T-Force GC Pro.  It might not have the pedigree of the Platinum P51 but it’s low price could be an advantage.  Thanks to the MSI MAG X870 Tomahawk WiFi, the two PCIe 5.0 drives can be benchmarked in both 2x and 4x to add a few more data points.

Yes, There’s AI Involved

To keep it short, the SK hynix P51’s 2 million hours MTBF is to reassure those creating large language models that the drive will keep chugging even when left running under load 24/7.  Since the vast majority of  LLM work will actually be reads, it makes sense that they are not pushing a TDW rating, though it would be a nice data point to have.  

With that out of the way, the P51 is also built for gaming and it’s physical design and thermals will mean it is right at home in a PS5.  The majority of the work done in those systems will also generally be read heavy, unless you happen to be doing a review of it and need to wipe it and load it down with files again and again in a short period of time.  If you do happen to be involved in a lot of copying the variable SLC cache seems to go up to around 500GB on the 2TB model, indeed there was no evidence of throttling during my internal testing.

PCIe 5.0 x4 Versus PCIe 5.0 x2 Versus PCIe 4.0 x4

The MSI MAG X870 Tomahawk WiFi used in this test has some shared PCIe 5.0 lanes which makes it easy to toggle the USB 4.0 ports on and off which cuts the lanes available to the second PCIe 5.0 M.2 slot in half.  That means you can see the effect those extra lanes have on bandwidth and the math works out more or less perfectly.  A single PCIe 5.0 lane should provide twice the bandwidth of a single PCIe 4.0 lane, 4GB/s as opposed to 2GB/s so you would expect to see a PCIe 5.0 x2 offer roughly the same bandwidth as a PCIe 4.0 x4 connection.

As you can see in the CrystalDiskMark benchmarks that inference is vindicated by the results.  The IOPs are unaffected, so even with a PCIe 5.0 drive limited to x2 you will still gain some benefit over last generation’s interface.

P51

TeamGroup T-Force GC Pro

SK Hynix P41

Direct Storage

3DMark has added a storage testing DLC that gives more detailed results than the full system test, providing insight into SSD to VRAM bandwidth, temperatures throughout the test and a look at what DirectStorage enabled transfers offer your system.

P51

Full results here.

TeamGroup T-Force GC Pro

Full results here.

SK hynix P41

The 3DMark Storage Benchmark is missing as it runs against the full system and the P41 wasn’t an OS drive during testing.

Full results here.

TeamGroup Pulls Out A Surprise

In the comparison below you can see that the SK hynix P51 offers higher performance in almost every way, except for one very interesting exception.  TeamGroup’s T-Force GC Pro actually shuffles data to your GPU faster than the P51.  Several other sites have seen the same result and while it’s hard to say why the Innogrit controller talks to VRAM more effectively than the Alistar there is no question it does.  The results of the Direct Storage off are merely amusing, as you won’t encounter those transfers often.

There is also the fact that an SSD which is not hosting your OS doesn’t have the transfer overhead of an OS drive, which is constantly being bothered by Windows and your other apps.  This suggests the GC Pro might be an interesting addition once you’ve filled your OS drive to 50% or more, as the GC Pro will forge a solid relationship with your GPU.

3DMark charts below or added above

The Heat Is On

In all tests, the three SSDs relied on the built in heatsinks that come with the MSI MAG X870 Tomahawk WiFi.  While they are built very well, they have an improved latching mechanism which is easy to use but one worries is also easy to break.  M.2 drives are not that hard to mount and adding a proprietary enhancement seems a little unnecessary, albeit handy when conducting a review.  The tabs that replace the screws show no sign of weakness, but it is worrying that if they ever do break it may be hard to MacGyver a replacement.

The first generation of PCIe 5.0 drives we saw wanted active cooling to perform at their best, thankfully that no longer seems to be the case.

10% Complete … 50% Complete … 90% Complete … 90% Complete … 90% Complete

In an alternate universe the green bar signifying the percentage left in a copy operation is accurate; we do not live in that universe.  We do inhabit one where you can use snipping tool to create GIFs so enjoy a minuscule slice of the transfer speeds witnessed while copying a Steam library, assorted game saves and a fair chunk of the Appdata folder to the SK hynix P51.

This is also evidence that the rare occasion of a Windows patch not being the cause of issues for all us beta testers.

For External Use Only

A couple of tips for those making use of SSD enclosures also surfaced from this review.  First off is the proper way to mount one for proper performance as Windows defaults to allowing you to unplug an external drive without ejecting it.  This is handy but can and will lower transfer speeds when you are moving large amounts of data back and forth.  You should search for Computer Management, launch it and take a peek at the Disk Management section.  Right click on the disk itself, not the volume and switch to the Better performance option which enables caching and will improve your transfer speeds.

The other consideration is that while the drives attached to your motherboard are enjoying a nice fresh breeze from your case fans, your external drive is definitely not.  It matters not how fast the drive in that enclosure can go, the defining factor is how much heat the enclosure can handle.  It will get impressively toasty under sustained transfers and you should find additional ways to move that heat away from your SSDs controller lest it throttle to speeds which would embarrass a purpose built external USB drive.

Greatness Requires Sacrifices

We arrive at the nub of the matter.  The SK hynix P51 is an amazing PCIe 5.0 SSD with both a custom designed controller and new flash which show the advantage of designing a drive completely in-house.  It also illustrates the problem of going on your own; expense.  The vast majority of SSDs use controllers designed by Phison or Innogrit and thanks to the economy of scale that means they can be produced at a lower cost.

At the time of this review, the TeamGroup T-Force GC Pro is $120 CDN, $90USD less expensive than the P51. To put it another way, the GC Pro sits at around $0.12/$0.09 GB and the P51 at $0.18/$0.14 GB, in clear violation of Ryan’s Law in all but one case.  You can add to that the fact that for gaming, the difference in load times between a PCIe 4.0 drive and a PCIe 5.0 drive can be measured in nanoseconds.  There are certainly applications where you will see a larger difference, or where nanoseconds quickly add up, which is why it is wise that SK hynix focused on longevity for these drives.  If you’ve joined the dark side and are hosting an LLM or arguing about the benefits of Proof of Stake the P51 is a solid investment.

The P51 is without doubt faster than any of the other drives tested here and essentially within margin of error of the Samsung 9100 PRO 8TB, which benefits from significantly more space.  It does represent a serious investment, which may be more than many pockets can handle, however it will stick with you as it has been built to last and you can bet SK hynix will honour their warranty.