Computer internet problem?

[Justin]

Okay so I have a problem with my computer in simple terms for some reason my computer will not receive as much Mbps as it should what i mean by that is when i go into task manager my computer will only receive 1-8 Mbps when it use to receive 15 Mbps+ (about 1 week ago or so) now a few things to note
1. I don't think it's a virus as i have scanned my computer with 2 different antiviruses and they both came up clean.
2. I have a wireless connection to my router
3. this has happened to my computer once before but fixed itself in less than a day
4. only 1 of my computers is affected by this my other one (in the same room) gets the correct amount of Mbps and it's a few years old (also uses a wireless connection)
5. I don't know if this is important but he have fiber optic internet

Thanks
-also if you need any other details are needed please let me know