This is what I think should be the next step.
1) Use a cross-over cable that has been tested before on two other machines that weren't involved in the first place. This isolates the cable as the source of the problem as well as router issues. I am well aware that certain computers do have automatic straight/crossover switching but I wouldn't recommend flirting with that when there are issues that probably won't benefit from additional variables.
2) Fire up a compatible Mac with 9.2.2 or earlier on it. OS X can also be used but .... Enable File Sharing, and for best results, test if the Mac will mount other computers besides the 605, just in case. I'd use manual addressing.
3) Configure TCP/IP with manual addressing on the 605.
4) See if the Chooser reports anything then. Chooser in my experience is the most huffy-puffy about showing available servers with OS X 10.3+ (or 10.0, although I didn't test 10.0 for long, literally like less than an hour). If it doesn't show up, try entering the Internal IP Address of the host machine (which is why I recommend manual addressing).
5) Most of the driver software for third party devices (admittedly, I only have personal experience with the UltraDock 16sce and the Farallon series of cards) do have a cable-test function in the diagnostic software.
6) In the TCP/IP control panel, find the Get Info selection from the File menu. There should be a MAC address reported there.
7) It is unlikely (highly) but possible that the card could be incompatible with OT (assuming you have OT 1.3 and ASC 3.8.x installed). Everymac says the 605 will go down to 7.1, so you could try making a 7.1NAD with MacTCP 2.1 and try that.
All this and more is explained in detail in the link in my signature.
1) Use a cross-over cable that has been tested before on two other machines that weren't involved in the first place. This isolates the cable as the source of the problem as well as router issues. I am well aware that certain computers do have automatic straight/crossover switching but I wouldn't recommend flirting with that when there are issues that probably won't benefit from additional variables.
2) Fire up a compatible Mac with 9.2.2 or earlier on it. OS X can also be used but .... Enable File Sharing, and for best results, test if the Mac will mount other computers besides the 605, just in case. I'd use manual addressing.
3) Configure TCP/IP with manual addressing on the 605.
4) See if the Chooser reports anything then. Chooser in my experience is the most huffy-puffy about showing available servers with OS X 10.3+ (or 10.0, although I didn't test 10.0 for long, literally like less than an hour). If it doesn't show up, try entering the Internal IP Address of the host machine (which is why I recommend manual addressing).
5) Most of the driver software for third party devices (admittedly, I only have personal experience with the UltraDock 16sce and the Farallon series of cards) do have a cable-test function in the diagnostic software.
6) In the TCP/IP control panel, find the Get Info selection from the File menu. There should be a MAC address reported there.
7) It is unlikely (highly) but possible that the card could be incompatible with OT (assuming you have OT 1.3 and ASC 3.8.x installed). Everymac says the 605 will go down to 7.1, so you could try making a 7.1NAD with MacTCP 2.1 and try that.
All this and more is explained in detail in the link in my signature.