Ethernet Specification and Cable Length

I have 3 new computers in my house. The ethernet cards in all 3 of them fail to drive a cable even close to the length in the specification, which is 100 meters. One machine is a laptop, I can accept that it does not need to drive a very long cable, it has wireless. The other 2 machines are desktop models though. They should be able to drive 50' cables. Neither one of them can. One of them will function on a cable of about 25', but the data rate is slow, a lot of frame errors and retransmissions.

It seems to me that the hardware vendors are cutting every corner they possibly can to try to make money in a commodity market. You would think that they would still produce hardware to the specification.