This one looks worth for ssd upgrade. .

No kidding about the heat build up in an NVMe M.2 drive--for some reason I kind of glaze over "heat" information on these drives (even HH's nice thermal information!) when I read these reviews. No more. Ran into my first problem with my EVO 960 250 GB NVMe boot drive. Something possessed me to run a custom Defender scan on C:\ (where the entire drive is scanned) and lo-and-behold I began seeing GSOD's (for various errors) suddenly in what has always been a rock solid system. Doing several things I finally narrowed it down to heat: first, I scanned my entire C:\ drive several directories (8-10) at a time, all the way through the drive contents without incident, to make sure the drive was clean of virus/malware. Then to double check I copied my entire C:\ boot drive (only thing on it is Windows and my utility programs) to a folder on one of my HDDs--and scanned it again, there, without incident, in a custom scan, just to make sure. No problems. So it has to be heat--and only the heat generated by invoking a custom drive scan of my NVMe boot drive. For any other lesser drive task, the heat never reaches a high enough temp to first freeze the system and then hard lock it. Only way out is the reset switch. I'd never done a custom scan on C:\ since installing the 960 as my boot drive, because I figured if I ever wanted to I could, and because Windows does background AV/Malware scanning all the time--to frequently pop up messages like, "Your system has been scanned 9 times and no problems have been found," etc. It's in the m.2 slot @ 4x and sheathed with the MSI heatsink that was included with my motherboard--but in the case wherein the drive is called on to run continuously for several minutes--the sheath heatsink is not enough, at least in my case. I was actually able to predict the heat build up by noting that after a certain number of files/directories were scanned the drive would begin to slow down noticeably--just before the inevitable lock up--unless the scanning stopped before that tipping point was reached--at which point the drive would cool over a span of 10-20 seconds and operating performance returned to normal. I'm debating on whether or not to do anything about it, though. For all other operations, the drive functions perfectly. So, I either get a better heatsink or avoid doing a Defender custom scan of my entire C:\ drive! Still collating...;) I really don't *need* to custom-scan C:\...still...

@waltc3 I have a 960 evo 250gb without a heatsink. I never do any full or custom scans. Just everything default for defender. Run malwarbytes default settings scan once a month. Never have a heat issue. Its my OS drive.