cchavoc,
Because your post is in "Networking" versus "Wireless Networking" I am led to believe you are both using "wired" connections. Correct?
Has he ever had faster DL speed? At his home or at yours? What AV software is in use - what happens to DL speeds if the AV is stopped?
That said, has he checked that he has up-to-date drivers for his ethernet card? Or has there been an recent driver update? Maybe the newer driver has a problem of some sort - especially if he has had higher DL speeds in the past.
Device Manager shows many possible settings/configurations for installed network adapters. Has there been any known "tweaking" in hopes of gaining improved performance or speeds?
Suggest that you post the Make and Model of his network adapter - someone may recognize the problem accordingly.
As for his machine being "better" that can be a relative issue. Performance is driven by a variety of factors. He may not have control of some existing "bottleneck".
Please add some detail. Thanks.
Take care,
Ralston18