Dual-ethernet port Network Cards -- Question

I was looking on Newegg for a dual-port Network card so that while in residence at school, I can run my highspeed to my computer, and then connect my Xbox 360 to the second port for Xbox Live. We won't be allowed to use routers or switches while in residence, assuming because they don't want several people sharing a single internet connection.While looking on Newegg for one of these cards, I was shocked to find that they cost around $120. Especially considering how you can get a single-port network card for $10. I was also surprised in that a motherboard I owned quite some time ago had two built-in ethernet ports, and the whole motherboard cost less than $150.I'm currently looking at other options, because I will switch my ethernet cable back and fourth between my computer and my 360 before I ever pay $120 for a card. However, I was just told that if I install two single-port network cards into my computer, it works the same as a single double-port.Can anyone confirm this? If I was to install two network cards into my PC, would I be able to connect my highspeed into one card, and my 360 into the other, allowing me to connect to live? Thanks in advance.Dual-ethernet port Network Cards -- Question
Can't see a prob, but you will lose two PCI ports and if you have a big GPU card you'll have to make sure you have enough room to keep it cool.