Will buying a SSD improve my fps drops?

Current Specs:

CPU: AMD FX-8350
RAM: 8GB
OS: Windows 10
GPU: AMD Radeon R9 200 Series 2GB
Hard Drive: WESTERN DIGITAL WD10EADS-65M2B1 1TB 5400 RPM 3.5" SATA HARD DRIVE

I've had my hard drive since 2010 so it's pretty outdated. I'm getting insane fps drops/freezing when I open strong boxes, high density mob effects, etc. I'm wondering if I'll be able to fix these issues if I just upgrade my 7 year old HDD to a SSD? Or are my specs not good enough to be able to handle POE? Any info helps, thanks.

5400RPM drives are kinda slow - even a 7200RPM HDD would be a big improvement in loading times and general system responsiveness. If you want to put Windows, Path of Exile, and a few other things you use a lot onto an SSD I definitely wouldn't talk you out of it. Hang onto the HDD, though - you should be able to use both. You might be a bit tight on space otherwise.

My advice would be to expect an SSD to make FPS drops and freezes drastically less severe and shorter, but not necessarily go away entirely. Strongboxes in particular will cause a brief, momentary freeze. Remember that it won't only help with PoE - an SSD is very nice to have.

If you're not sure which video card you have, Speccy might be able to help.

It won't. SSD just reduces loading times and fps drops upon loading new stuff(pretty common to crash during lab runs while using HDD due to that).