I have put some large files up for a few of my user account members to download over the internet (100-300MB). They are only able to get download speeds of about 60-100Kbs.

I tested my bandwidth from the server last night with the tools available on DSLreports.com (which I have used for years), and I am consisitently getting upload speeds of 1000 to 13000 KBs. I am using Comcast premium cable service.

I also looked at CPU utilization and it is about 4% when someone is downloading.

Is there a setting somewhere in the server that throttles downloads? Any ideas as to hot to speed this up?

Could it be the cable router?

Also, could I replace my cable-provided router with a better one?

I have found DSL reports to show upload speeds that i could never reach in real world tests.

I bet you are seeing a difference between kiloBIT and kiloBYTE. Check the tests you are running and see if it's KiloBITS per second.

1000KiloBITS per second = 125 KiloBYTES per second