Did not set stop watch but just a few seconds to open. BTW make sure before you unzip, have not checked to see it makes a diff, but unblock. Doing that for zip file unblocks all files in the archive but since only 1 probably does not make any diff.
As posted early. Using task manager to at least do wait chain analysis for Su and see if it is waiting on other processes. Typical group think 
The only speed advantage you get is bringing bits into RAM from disk or saving when bits go back to drive, log files and paging files etc. Other wise RAID 0 or 1 should be about same they handle same # bits. IMHO choice is bad to have two small drives. I would replace 1 ssd with a big platter, have op system on SSD, make image of it( There are free image makers) , do good backups of data on platter and never have to re install OP system again.
Iām with Dan. It appears to be to do with the Outliner. Have you tried closing Outliner?
The Outliner is notorious for slowing operations down. It should never be open, unless you are specifically using it.
This would include:
Inspecting group and component nesting.
Selecting objects (especially hidden ones you canāt select in the model view.)
Moving objects from one edit context to another (when it cannot be done easily in the model view.)
Close the Outliner or roll it up before intensive model operations.
Thanks for this info. Yes, the machine is slowest when the outliner is open. You have found the heart of the issue. However, our models all work great on all our other machines with the outliner open. The outliner is critical to use with our standards since components and groups are deeply nested.
I just finished a remote session with the manufacturer. I was able to log onto the same machine with very similar specs they have in stock and try our model. This remote computer has the same C drive but no D drive. The model and outliner were very fast - no issues. They he installed a D drive smaller than mine and it slowed a little - eventhough both sketchup and the model were on the C drive. My computer is still 10x slower though.
They donāt know why. He suggests it might be a windows installation issue. Instead of re-installing and updating all our files again, they are going to send a replacement computer. This time however Iām getting one C drive with RAID 0, but 1TB (2-512) and no D drive as one of you suggested. I figure I can always add a D drive and our files are backed up well.
So I hope it works out. Iāll let you know. Thanks for all your help.
As I posted above the use of SSD will not give you a big boost in speed. Hard drive is used for storing data like when you save a file or when you open one the data is read from drive into RAM. In some cases the windows memory manager will write to the drive if it runs low on RAM to run the threads.
I gave you some very specific TS suggestions but guess that was wasted time.
If you contact the System Internals or Defrag tools guys at Microsoft the may have some trouble shooting suggestions for you. They have a whole suite of free TS tools you can use and may ask you to collect some data using those
This is example of what your are ignoring in task amanger ref above
Apologies for not acknowledging your suggestion. I am aware of the difference between ROM and RAM. My IT previously analyzed the task manager as you mentioned. I will look into the TS tools and Microsoft System Internals or Degrag tools departments. Thanks again for your input - very much appreciated.
there is no ROM involved, working memory as well as the SSD are Random Access Memory.
Thanks again for your help
If you close outliner does the slow-down persist? I find that if I keep outliner open when I work it tends to slow everything down.
Six days late to the party. See the following post above:
To which he responded 4 days ago ā¦
Ha! Whoops, thatās what I get for skimming the thread instead of reading it properly. At least I was in the ballpark with my suggestion 
Just as a gut check, I opened your file on my MS Surface Pro 3, SU 2015 and the file file opened in about 4 seconds and is smooth to move, translate, rotate. Donāt think it is the SSD or the graphics card.
System Details:
MS Surface Pro 3,
8Gb RAM
512Gb SSD,
I7-4650 @ 1.7Ghz,
Intel HD5000 GPU,
SU Version 15.2.685 64-bit
how did you get my file?
Do you mean this file offered as a test above?:
The file will open quickly but it was meant to test the processor by running the sandbox on it after it is opened. That should take about 2 minutes on a similar spec PC as the OP.
This is definately an issue with the NVidia GTX 980 card (probably driver related)
I recently upgraded just my video card from an AMD HD6800 to an NVidia GTX980, and from that very moment, Sketchup instantly became very very sluggish.
I have been unable to solve it even though I have tried playing with various driver settings.
I tried switching back to the AMD HD6800 and then it runs just fine and fast again, I still stick to the GTX980 though as its waaaay faster for everything else, just not Sketchup 
Hopefully this is resolved at some point with a software update from either sketchup or nvidia.
NVidia cards are general regarded as ābetterā !
Do you have the latest drivers installed ?
Is the card settings [in its control-panel] set up to let the 3d program decide on its own settings ?
What are your SketchUp Preferences > OpenGL settings ?
Perhaps a screenshot would help ??
I spent some time this past week in the Nvidia forums because my Dadās notebook has been having the GeForce driver repeatedly crash.
There are issues with the Nvidia drivers. And there are some hotfix releases available. The announcements of these hotfix releases are done via forum sticky/pinned posts.
Also for some issues, is may be necessary to rollback to a specific previous version.
Nvidia cannot fix any application specific driver issues unless they know about them, so please report issues.
Didnāt someone figure out the Windows defender can slow down SketchUp? It might be worth a try to make an exclusion for SketchUp.
Can you post your file and also give us complete info on the machine you are using including the manufacture, SKU version, memory, operating system including the version ( Hope you are not using windows 10)