Can overheating SSD cause steady performance degradation?

[flukelee]

I have an upgraded HP Pavilion laptop that has been having heat issues since I bought it, specifically with the SSD overheating and causing the computer to freeze without recovery. Apparently, this is a known problem (http://www.tomshardware.com/answers/id-3263545/ssd-overheat-computer-restarts-extremely-important.html).

I had the SSD replaced under warranty, and got a pair of external fans to help cool things down. Now, under normal load (not gaming, just web browsing), I have brought the SSD temp from nearly 60C to 48C (118 F), according to CrystalDiskInfo. So far, no more crashes and restarts!

However, I have noticed a steady decline in benchmarks and speed of my new SSD. Could this be related to heat issues? Is this something I need to be concerned about?

Benchmark 1 month ago: http://www.userbenchmark.com/UserRun/8271441
Benchmark yesterday: http://www.userbenchmark.com/UserRun/8855259

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System hardware (with external fan running):
cpu: i7-7700HQ, typical temps: 58C to 88C (135F to 190F)
gpu: GTX1050, typical temps: 50C to 70C (120F to 160F)
SSD: PM961-256GB, typical temps: 48C to 54C
HDD: HGST-1TB, typical temps: 35C to 37C

(note: I am a new user to this forum, so any corrections to my question are appreciated!)

 

[maxwellmelon]

well heat can slow it down but also the fact your down under 20% free space left on it also will slow it down some too... don't know about the m.2 format but on regular Samsung SSD sata drives you leave a bit of the drive unpartitioned so it can use the space for garbage collections and stuff mabe some one can shed some more light on this issue

 

[mdd1963]

So from 2.02 GB/sec reads down to.... to 2.01 GB/sec sequential reads?

1100 MB/sec writes to 970 MB/sec?

 

[flukelee]

well heat can slow it down but also the fact your down under 20% free space left on it also will slow it down some too... don't know about the m.2 format but on regular Samsung SSD sata drives you leave a bit of the drive unpartitioned so it can use the space for garbage collections and stuff mabe some one can shed some more light on this issue

Thanks for the pointers, I ran disk cleanup and cleared about 50GB of windows.old files. Also as pointed out by @mdd1963, I was looking at the percentile ranking not actual read/write speeds which are nearly the same as before. I guess the PM961 SSD has a very tight range of real world operating speeds.