HDD as boot drive SSD as storage

The SSD will be just as fast. But it won't help with the speed of the OS (or general usage). Many programs can't install to it. Even those which do. Often install files to the OS drive. Even those which install to the SSD completely still make many calls to the OS. So, most won't respond any faster.

As far as raw Read/Write speed, IOPS, &c. That remains the same. It's just you won't get much benefit from it.
 

InvalidError

Titan
Moderator
The main reason people use SSDs is for programs and OS to launch faster. Using an SSD for data only makes sense if you have a large data set for something that requires very high random read/write IOPS, such as a high traffic database or web server.
 

InvalidError

Titan
Moderator

As long as you have enough RAM, it doesn't matter how many "calls to the OS" software makes, only the first call that involves a new DLL/API will ever incur the overhead of loading the necessary DLLs from HDD that haven't already been loaded by something else during boot, all others will be served from memory/cache.

I have 32GB of RAM and putting an SSD in my system makes basically no difference beyond boot time and the time it takes to launch software for the first time between reboots. Since I only reboot my PC once every month or two under normal circumstances, I rarely get to see the benefit of my SSD.