To test the NIC's at the various bus speeds, we transferred a 500MB dummy file between two computers using a Linksys 4 Port Router (it has a 10/100 Switch integrated). Obviously the D-Link was the slowest running at 10BaseT, the file transfer took forever!Each NIC was also subjected to one hour of web surfing.

FSB	3Com	Allied Telesyn	DLink	Accton	Smartlink
133 MHz	Pass	Pass	Pass	Pass	Pass
150 MHz	Pass	Pass	Pass	Pass	Pass
160 MHz	Fail	Pass	Pass	Pass	Pass
166 MHz	Fail	Pass	Fail	Pass	Pass
170 MHz	Fail	Pass	Fail	Fail	Pass
173 MHz	Fail	Fail	Fail	Fail	Pass
176 MHz	Fail	Fail	Fail	Fail	Pass
177 MHz	Fail	Fail	Fail	Fail	Fail

Here's a MHz breakdown on where the cards stand...

NIC	Max PCI Speed
3Com 905CX-TXM 10/100	150/4 = 37.5 MHz
Allied Telesyn AT-2700TX 10/100	170/4 = 42.5 MHz
DLink DE-528 10Base Combo	160/4 = 40 MHz
Accton 10/100 EN5038	166/4 = 41.5 MHz
Smartlink 10/100	176/4 = 44 MHz

As we see here, the 3Com maxed out at a PCI speed of 37.5 MHz while the Smartlink 10/100 hit an insane 176 MHz FSB. It's rather surprising to get these results, usually the more expensive products have higher quality components.

The Allied Telesyn AT-2700TX 10/100 did pretty well, using a AMD chipset. Perhaps AMD is trying to cater towards the enthusiast in every way. Even though we don't use that 10Base NIC anymore, I threw in the D-Link DE-825 because it seems a lot of broadband companies out there are using these as standard issue for their clients. As for the bottom of the barrel NIC's, those generic ones that you can pick up for around $20, the Accton and Smartlink work pretty well in terms of overclocking.

So what can we conclude here?

For enthusiasts who are looking to push their systems to the max, don't overlook something as trivial as a network card. As the above demonstrated, the 3Com would limit a system to 150 MHz FSB while the Smartlink went as high as 176 MHz! If you're planning to overclock a server, the Allied Telesyn is quite feature rich, it has WoL (Wake on LAN) and a boot ROM (sold separately). If you want to push your computer as high as possible while still keeping the ability to connect to a LAN, try out those Smartlink 10/100's - they seem to handle the high speeds pretty well!