I agree with swimmer....... dial up has no real good tweaker due to the fact that all C.O. lines are different.....depends on,,,are you coming out of an ESS office or an older step office ....or....etc. so it is really trial  and error but the truth is you can tweak to get whats best for your line.........the best improvement anyone can make for speed on any C.O. line is to hook computer up to line as close to mpop as possible.......(where phone company brings line to home) it is better to get the line before it goes all through your house(more wire slower connection) other than that your kinda on your own .......I do know that it is possible to make a lot faster than it is now.....but C.O. lines are capped.....FCC ...bull
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