Yeah, debauch, I was going to say something similar.

Things I would check:

1) Are you using real category 5 cabling for this connection, or did you jerry-rig some sort of flat-cable solution?

2) Did you make the cables yourself, or did you purchase them pre-made from a company that really knows how to correctly wire a network cable?

3) (I'll bet no one else has thought of this one.) Have you used any utility programs which adjust your TCP/IP network settings to "improve" speed for downloading or playing games on the internet? For example, programs which change your RWIN or MAX MTU settings? For that matter, have you hand-altered any of these settings in the registry based on reading a web page somewhere? Once, I had a friend who used one of these utilities. It improved his Quake ping times by some miniscule amount, but then it totally hosed his LAN connection, making it nearly impossible to send and receive files via ethernet.

I'll bet it's the third one. Anyone want to make a wager on it?

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Tony Fabris