11-02-2015, 10:38 AM
https://www.pugetsystems.com/labs/articl...Drive-725/
Now the 950 Pro M.2 is overheating, although not quite as bad as the SM951 and XP941.
Now the 950 Pro M.2 is overheating, although not quite as bad as the SM951 and XP941.
Quote:To see how hot this drive gets, we did a simply file copy of ~205 GB worth of ISO files. As you can see, the 950 Pro does run cooler than the SM951 by about 5-12 ºC, but it still reached a peak temperature of 98 ºC on the controller chip (the storage RAM itself does not get anywhere near as hot). This isn't doing hours of benchmarking in a closed box either - just a simple file copy on an open test bench. Doing this, the 950 Pro hit 97 ºC after only about a minute and 98 ºC after about 3 minutes compared to the SM951 which hit 100 ºC after about a minute and 110 ºC after only about three minutes.
What is really interesting is that until the 950 Pro hit 97 ºC, both it and the SM951 had nearly identical temperatures. In addition, during this period Windows reported identical file transfer speed of about 700-800 MB/s for both drives. After the 950 Pro hit 97C, however, the transfer speed on the 950 Pro dropped to around 400-500 MB/s which it maintained for the duration of the file copy. The SM951, on the other hand, sustained the 700-800 MB/s transfer speed except for around the 150, 190, and 230 second mark where you can see a slight dip in temperature. At each of those points the controller on the SM951 hit 111 ºC for a split second and the paused the file transfer until the temperature dropped to below 100 ºC.
Due to the fact that the Samsung 950 Pro throttles sooner than the SM951, we actually saw much lower sustained performance on the 950 Pro than we expected. To copy all 205GB worth of ISOs, the 950 Pro took about 365 seconds while the SM951 only took about 274 seconds. This translates to a sustained file copy performance of about 562 MB/s for the 950 Pro and about 748 MB/s for the SM951. In other words, while the Samsung 950 Pro does have lower temperatures than the SM951, it achieves this by being much more aggressive in it's throttling.
In our opinion, we actually prefer the earlier throttling on the 950 Pro. 98 °C may still be extremely hot, but it is much better than 111 °C. In fact, while Samsung even mentions throttling on the overview page for the 950 Pro:
Quote:The 950 PRO also features Dynamic Thermal Throttling Protection technology, which controls the temperature of the device to reduce overheating and maintain a high level of sustained performance.Samsung's overview page for the 950 Pro makes it clear that this drive is designed to throttle when the drive gets hot so the high temperature on the controller shouldn't impact the longevity of the drive. However, even if you are willing to trust that Samsung has addressed the high temperatures appropriately, you still will see a drop in performance if this drive gets too hot. And since that happens after only about a minute of sustained file transfer, it is likely that most users will run into this throttling at some point.
If you want a high performance drive that is able to achieve the advertised performance over prolonged periods of time, we would highly recommend using this drive in combination with a PCI-E adapter that includes a heatsink (we use this adapter ourselves) or otherwise affix a heatsink to the controller chip to help dissapate the heat.
...
The biggest issue we have with the 950 Pro is one that seems to come up often with high performance NVME drives - temperature. The 950 Pro does run cooler than older NVME drives, but the controller still easily hits 98 °C at which point the drive throttles. We were hoping that the move to V-NAND would improve the controller temperature, but it appears that this is not the case. All this really means is that if you want to be able to maintain the full speed this drive is possible of at all times you will need to use a M.2 to PCI-E adapter with a heatsink. On the other hand, Samsung publicly advertises the throttling capability of this drive so if you are willing to see some performance throttling it should be completely safe to use it without a heatsink if you wish.