Using an old Windows keyboard on a Macbook I recently found my old mechanical keyboard and I want to use it on my Macbook Pro. It still uses an old PS2 connector so I went out and bought a PS2 to USB adapter. 

When I plug it in, the lock lights on the side simply light up once and then I can't use it. The keys do not work and the keyboard identifier utility from System Preferences does not recognize it.

I'm guessing I need some sort of driver but where can I find it? It's an old A4Tech KeyWorks Office keyboard.
I have heard that all USB/PS2 adapters are not created equal. Some work some don't. But you would probably cost yourself more time and effort getting a working adapter than just buying a cheap PC USB keyboard.

I use PC USB keyboards on Macs all the time and they work a treat. I can get a used (Dell) USB keyboard locally for about twelve bucks. As cheap as they are you could spend that on two adapters easily, not to mention time spent futzing with it...