Sporadic DSL speeds

I've been having sporadic speeds on my DSL for several months, and I mean speeds from .10 Mbps to 8.20 Mpbs, a service guy came out and fiddled with some outside wires in the phone box, seemed to help some but still had the same problem, yesterday it was running real slow so tech support suggests I go get a new wireless modem so I go to the main building and they give me a CenturyLink PK5001Z, I installed it and got instant 8.20 Mbps speeds and it was very fast, instant webpage loads and I watched Netflix on my wireless Roku all night without problem, now today my speed went down to 5.0 Mbps this morning and now has dropped to 0.1 again!!!! Any suggestions?


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Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 7 Home Premium, Service Pack 1, 64 bit
Processor: Intel(R) Core(TM) i5-3570K CPU @ 3.40GHz, Intel64 Family 6 Model 58 Stepping 9
Processor Count: 4
RAM: 16274 Mb
Graphics Card: Intel(R) HD Graphics 4000, -1984 Mb
Hard Drives: C: Total - 171602 MB, Free - 101428 MB; E: Total - 476936 MB, Free - 293962 MB; F: Total - 476936 MB, Free - 202337 MB;
Motherboard: Gigabyte Technology Co., Ltd., Z77-DS3H
Antivirus: Microsoft Security Essentials, Updated and Enabled