The best replacement for high speed is dsl.

The best alternatives to high speed are rated as following:
★★★★★  dsl
★★★★  broadband
★★★  standard hdmi
★★  full speed
★★  dial up
★★  full speed usb
★  standard speed hdmi
★  high speed
★  wireless internet
★  standard hdmi cable
★  broadband internet
  low speed
  verizon dsl
  fine scrubbing
  cable internet
  dial-up
  broad band

Your alternative for high speed is not listed? Suggest!
Speaking about high speed, one probably shouldn't forget about internet.

Other search terms related to high speed and their ratings are:
★★★★★ internet
You have in mind a companion for high speed and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of high speed in all years. Click on graph for more.
high speed
dsl
broadband