While you can use certain benchmarks to **prove** that one SSD is superior than another....But if you look at how SSDs are tested,,, the "real life" differences between then are so small as no one going about their daily routine would ever be impacted. If you took a job as IT manager and recommended an office wide replacement of SATA SSDs for PCI-E based SSDs for SSDs (or even SSD's for 7200 rpm SSHDs or HDs) because it would increase "productivity" ... and agreed to prove it, with your job at stake ... start updating your resume now. There are instances where it does have a ROI such as photo / video editing, animation and rendering for example.... but in your typical home of office, it's not a life changing experience.
For example what does a boot time of 17.6 versus 18.4 secs do for you ? How is your life changed if BF1 loads a level in 16.8 vs 18.2 seconds ? ... or Watch Dogs to in 45.8 vs 46 seconds ? Not mine ... a new level loading usually means a trip to the bathroom or a snackie. and if not, Im loading a map of the new area on a 2nd screen. Life is a lot less stressful and results actually relevant when you focus on things you actually do on ya PC rather then benchmarks and other things you never or rarely do . Time to run a backup or AV scan .... who cares, I'm sleeping. Time to compress / uncompress a large amount of files ? ... never done that. Time to install Itunes .. 14.2 vs 15.1secs ? ... You do that once every 3-4 years ? MS office Installation ... well that took 166.7 seconds on the NVME Samsung 970 EVO and 55.6 secs on the SATA Samsung 850 EVO ... but again, who cares... a once every 3-4 years thing and you are doing something else while it happens. Aside from user bragging rights, and marketing folks, SSD speed differences really are not having a real impact on productivity outside a very small % of boxes using aforementioned applications
That being said, of course people with certain afflictions .... nerds, engineers, IT folk (aka folks like TPU forum members) ....
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will almost certainly have 1, more likely 2 or more, on their own boxes. Our SOHO network has at least 1 SSD and 1 SSHD on every box, about half have 2 ... On the SO side (Small Office), the main activity is CAD. Back in the day, the state of AutoCAD was such that $1,000 SCSI 10k 1.0 GB Hard Drives were the norm ... today file loading from SSD , SSHD and HD is indistinguishable. On the HO (Home) side, sure we can measure tiny differences in game loading, but does it matter if a level loads 2 seconds faster when you are using the break to grab a sammie, hit the "can" or open web pages, chat on discord ? Worrying about which SSD is faster is kinda like wondering if you should get a sports car because you are worried about being late for work. Whether I take the SUV or the Porsche to a job site, Im still going to get there about the same time.... if you ate 20 minutes late instead 20 minutes and 11 seconds late, won't change anything. How fast i could get there if there were no traffic and no speed limits really isn't that important because that's nor reality. Our approach is:
a) Look at the things you do every day and determine the real impact on productivity
b) Set a performance threshold at which a faster product actually has a financial ROI. If you do photo / video editing for example, if you are currently completing X projects in 8 hours .... if you can reduce that to 6 hours, that could increase your income by 25% and that investment will be paid off rather quickly.
c) Look at what you are doing on that 0.8 seconds it takes Windows to boot or that 0.2 to 1.4 seconds it takes a level to load .... Can you get something done in that time ? if not, then you are not really getting anything from your additional investment in a faster storage device.