you could buy a cheap pci ethernet card for your pc, and use internet connection sharing (ics) and a utp crossover cable to connect your ps2. However if when you say old you mean ooooollllld it might not operate fast enough to transmit the data fast enough. i think when we first got our ps2 online we were using 1300mhz so im not sure how low you could go before it was affected, it would probably also be dependant on your FSB speed, but as long as ur pc is no more than 5 years old it would work, im pretty sure