Computer starts slowing down, then freezes after ~5 hours

This problem has been happening for about 6 days now. Every day, I turn on my computer, and after about 5 hours of usage, it starts slowing down. I check task manager, and it says 7 gigs out of my 8 gigs of RAM is being used, but under the processes, the most RAM-consuming process is google chrome, but it only uses about 200 mb. After a while, my computer eventually just freezes and I have to force shut down my computer and turn it back on.

Specs:
CPU: Intel Core i5 4430 3 GHz
RAM: 8 GB
GPU: Radeon HD 7770
Storage: 1 TB HDD
PSU: Corsair CX500

It could be almost anything, hardware or software, depending on what you have installed.

You do mention Chrome. It's been a memory hog for awhile, but more importantly, check your Chrome add-ons. Many times they are the real culprit.

Here's a bunch of sites that have suggestions on helping with Chrome's memory usage.

chrome memory hog 2014 - Bing

By the way, have you run your system and only used IE or another browser instead of Chrome? That way you could see if Chrome is the culprit.

After using only firefox the entire day, I am still encountering the same problem. I'm not sure if this is due to a memory leak of some sort, or physical hardware that's causing the problem.

If your browser is on continuously, close the browser once in a while for it to clear the Browser History and reduce memory load.

It's not on continuously but clearing my browser history does not help. I should mention that when I startup my computer, my computer starts using ~5 gigs of RAM right away and slowly increase to 7, and then freezes.

Check your Startup tab in Task Manager for programs starting that don't need to, you could start them on an as needed basis.

I don't have any program that runs on startup besides my catalyst control center.

Can you post a screenshot of the Startup Tab of Task Manager and Memory under Performance Tab?

I see what you mean by your RAM issue.
Towards the bottom of the page Open Resource Monitor and see what is high there.
Hardware reserved seems to be high, what is attached to your computer and what is the make and model of your computer?

the highest processes are chrome and skype, but they don't seem to be the problem as I don't even start them up some days and I still have the problem. By the things I have attached to my computer, do you mean things like my mouse, keyboard, speakers etc? My computer is a custom built from cyberpowerpc.