Cat5e vs Cat6 cables

There is a great deal of debate among people about whether new cabling installations should use Cat5e or Cat6. Many people incorrectly assume that by running Cat6 they will then have a Gigabit Ethernet. However, in order to achieve true Gigabit Ethernet speeds, every single component on a network must be gigabit rated, such as the switches, hubs and network interface cards. This isn't to say that there aren't differences between Cat5e and Cat6, however. The general difference between category 5e and category 6 is in the transmission performance. While Cat5e can support gigabit speeds, Cat6 is certified to handle gigabit Ethernet. Additionally, the Cat6 specification is better suited toward environments that are generally unfriendly to twisted pair cabling. This includes areas that have lots of interference from things like power lines, lights, and manufacturing equipment. Still, for most applications, Cat5e is perfectly suitable and preferable to Cat6: it is more economical and performs almost as well. However, if you can be certain that all the components on your network are gigabit rated, and the volume of the data being transmitted calls for certified gigabit performance, then Cat6 is the way to go.

source: networkcablingdirectory