I'm going with it failed or is not configured right. I would check with Belkin and be sure the firmware is current on the router.
You don't need another cable to check the modem as you can use the cable from the modem to the router to test with. Be sure to power down the modem, then move the cable from router to PC then power up the modem, wait for the lights to stop then power up the PC. Test.
Same when going back to router. Power off modem, router and PC then move cable power up modem, wait, then power up router, wait then power up PC. Test.
I brought a Belkin N150 router and an Arris Touchstone SB6183 modem from Time Warner to Comcast - both worked fine on TWC, but now I'm only pulling about 0.3 MBPS right next to the router. I don't have an ethernet port on my computer to check the modem, but I have spoken with Comcast who says it is pulling about 12 MBPS. The router signal is strong but the internet is slow.
I have tried:
-Rebooting
-Factory resetting both modem and router
-Switching Channels
-Cloning Mac Address
I'm out of ideas. What else can I try?

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