Why SSD ? SSD Vs. HDD - Benefits and Advantages of SSD over Hard Disc !
Any PC, Laptop or Desktop, is basically a Computing Gadget. This Gadget takes Input - Process it - and Gives Output. This Flow of Input - Processing - Output is Cyclic and The Entire Process Rotates Millions of Times within a matter of Few Seconds. Components that play the main role in this process are - CPU RAM and HDD (or SSD if available).
The CPU and RAM work at extremely high speeds as compared to HDD which makes the Entire Flow of DATA in The Process halts (or slow downs ) when HDD's Turn comes to play it's role. At times, such tasks even que up for HDD to process it.
SSD is about 10-12 times faster than HDD. Performance SSD may go as high as 20 or more times faster than a standard HDD. Thus If you replace HDD with SSD - The Whole process picks up momentum dramatically. This increases The Overall Performance of Any Desktop or Laptop by around 2-4 Times.
CPU Uses Ram to Communicate Which file is Required from HDD and HDD fetches that files and gives it to CPU. Most of such files sought by CPU are related with the operating system (windows or linux) or application software ( MS Office, Photoshop etc.).
In Case, You have SSD in The PC or The Laptop, It shall be configured as primary storage ( C: Drive ) - which is the default location of - all operating system and application software files.
You can have SSD and HDD together in any PC - You can have more than One of both of them also.
You may consider to buy one Grade Lower CPU and ADD at least ONE SSD of even the lowest capacity AND You will find the overall performance of The PC or Laptop better than The Two Three Grades Higher CPU with HDD combination. for example, i3+SSD may perform better than i5+SSD for the purpose of understanding.