my issues has been solved after changing the game I was downloading.Update your post to include full system hardware specs and OS.
Could be buffering of some sort - more information needed.
What tool or utility are you using to observe the downloads and "usages"?
Wired or wireless network/internet connectivity?
Make and model router? The router's logs (if available and enabled) may provide some clue.
Who has full administrative rights to your network router. You will need help from that person.