Comcast customers are used to seeing items on their bills like "Performance Pro" and "Blast 105" for Internet service, but it's difficult to find out what speeds are advertised with those services. Even more difficult is finding out what Comcast actually provisions your cable modem to allow. Thankfully the folks at DSLReports keep a chart updated with precisely this information. For example, Blast 105 is currently advertised as 105 Mbps down, 10 Mbps up, but modems with this service are provisioned for 131.25 Mbps down and 12.5 Mbps up. Check out the chart for everything.