I have the same issue of downloading large rar/zip files that are corrupted, anything from nvidia drivers and whatnot. Tried the following but no help:

1. rebooting everything
2. updating network drivers

And this problem is on all three of my machines. Anyone else has this?

There was a downtime on early Saturday morning, around 3 or 4am. After that, all hell broke loose. Corrupted downloads via http and even download managers. Especially zip/rar files exceeding 50mb. Torrents with zipped files are fine though. My VOIP also down (didn't notice until somebody here mentioned it).