Cat 6 ethernet cables

Hi guys,

I am kind of new in the networking field, and my brother who usually deals with that stuff just moved.

Basically I have an Asus A7N8X-E MB with Marvell GB Lan and I need to buy the ethernet cable for it. As far as I understand the highest standard for ethernet cables is
Cat 6, and so I was thinking of buying this particular one from newegg.

http://www.newegg.com/app/ViewProd [...] 037&depa=1

My first, really newbie, question is wheter the above cable is ment for plugging into my Gb Lan and my wall jack.

My second question would be since the cables in my wall are Cat 5 I believe, wether that will prevent me from using the full capabilities of my CAT 6 cable since the signal is treveling from my brothers room to the router (cat 6) , through the walls, to my wall jack and only then through my cat 6 cable.

Thanks,
DrAmar

Ps. Why is the above mentioned cable only about 10$ S&H and the Belkin one from CompUsa 30+. Is Newegg really that much cheaper or is the Belkin one really that much better?

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