Installing Windows 10 on a combination of ssd and hdd

JBOD is basically putting them in, formatting them without a RAID array.

Alex Green, thanks for replying but i don't know a lot about raid so i'm asking
the ultimate goal is to install windows on a combination of ssd and hdd, not a must to be JBOD.. i don't know what form allows windows installation

It's tricky and I wouldn't recommend it.  BUT, if you create an answer file for Windows, you can change the location of Program Files at install time.  Doing so SHOULD allow well coded applications (meaning, applications that are coded to use what windows defines as program files) to be installed wherever you put it.  HOWEVER, I haven't even TRIED to do this for years.  If you are going to try, you would be better off TESTING first as you do this.

I junction my profile and any big folder to my mechanical drive so that I do not use up my SSD space for that

Lee W, MVP, I did the following

• Copy Program Files to hdd
• Change registry to match new path

but still didn't delete old one

• Delete original Program Files

Until now i only copied and matched the path, but im scared of deleting program files in c, don't know if windows still uses it after i moved it somewhere else

The problem with doing something like that is actually making it work.  Program files tends to be perpetually in use by Windows.  Changing it can be difficult if not impossible when you already have Windows installed.  For larger programs, you could do as Shaun suggests and move them to their own partition (GPT based disks can have up to 128 partitions) using a junction if you don't want to re-install.  

Personally, I limit what I put on C: and resign myself to C: being small (until I upgrade).  Move the Temp folders, Downloads folder, My Documents, Desktop, etc.  Things in Program Files don't generally grow too much over time.  But you download and create tend to accumulate.

You don't need to delete the programs folder, just rename it for your testing.  Call it xxx-Programs.  If all works ok, you are good to go.  Don't forget to test program installations and updates too, to make sure nothing bites you with a non conforming app.

Dont make any RAID, install Windows on SSD, then assign drive letters to hard drives, or mount them in folders.

Thanks everyone, every reply is helping
I think the easiest way is what Vadim suggested, mounting drives into the needed folders
but it has limitations such as a fixed partition size for 1 folder instead of sharing 1 big space
so probably making links is better for that matter...

but after reading some tutorials, I cannot somehow fully understand how to do it right
each tutorial has something strange about it, ones say the syntax is like that some say syntax is like this and so on.. some have different steps, some have a lot of steps
So the conclusion is im a bit lost


by the way i found out that adobe premiere is responsible for filling up C, it created +50GB of cashe in app data.
DESPITE THAT, i still want to continue with the process and get more space because 120GB is not exactly called a "big" space

well - i would install the os on the 120 GB SSD and only use the 2 TB drive
or is there a reason to use the 2 others?  320 and 250 do not add much space
also, are these laptop drives?  7200 rpm drives?
if unsure post the model

What do you have on PNY drive that it got so full? My C drive sits with 70GB used and it did not exceed this size in 5 years.

Vadim, thanks for the assistance that's helpful

But sorry if i wasn't clear, i meant symlinking  into another drive instead of mounting a drive
Result: both x64 and x86 program files will share the same fixed space instead of having separate halfs each


EDIT: I'm thinking again... I might save time and stick with mounting drives instead of symlinking folders...

Although what i wanted was a way to create a JBOD and install windows inside it so it automatically starts using the second drive when 1st fills up
but according to some searching, this makes the disks dynamic thus halting and crashing windows installation

EDIT: I'm thinking of raid 0

I would simply assign it another drive letter, then whenever you install something, you can easily decide which one to use, looking at how much space is left on each. Like I did on my computer on the screenshot. Plus, then you have more control: such as, if you are going to install your favorite game that you play every day, and which on startup reads gigs of files, you probably will want it on your fastest drive, the SSD, so it will start faster. On the other hand, files and programs that you use only occasionally and one by one, such as your documents or pictures, you can install on a slower drive.

By the way, today's applications often can be easily moved to another drive. That's because most of them are .Net applications, and one of the goals of Microsoft when designing .Net framework was exactly that, to be able to install programs by simply putting them in the folder and running from there, so less dependency on the registry and such. There's great tool called TreeSize, https://www.jam-software.com/treesize_free/, you can inspect what is taking how much space, and quite possibly simply move some programs to another drive.