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Thread ID: 134343	2013-06-22 05:50:00	Cat 5/5e network cable.	Nomad (952)	Press F1

Post ID	Timestamp	Content	User
1346661	2013-06-25 03:12:00	TLDR; Cat 5 can do GigE and always could. Wow, lot of misconceptions here! Cat 5 cable and connector is designed to operate at 100MHz. So technically you can only get 400Mbps when using all 4 pairs Cat 5e cable and connector is designed to operate at 150 MHz. So can reach 600Mbps when using all pairs Cat 6 cable and connector is designed to operate at 250MHz. So will operate at true 1Gbps Yes you can use old Cat5 cable on Gigabit port. The port will negotiate 1Gbps but can only operate at 400Mbps sustained error free throughput. rubbish, GigE was designed to work on CAT 5 which yes is rated for 100Mhz but it uses clever modulation to achive a similar effective frequency as 100M and therefore can run on the same cable for the same distance. Mhz <> Mbps (an extreme example a phone line works on 0-4Khz and can achieve 64Kbps in that band or 33.6 if it does 2 A-D conversions). It can and does work at full speed without errors for up to 100M on CAT 5. Cat 5e and CAT 6 were designed to improve the crosstalk and noise charateristics of CAT 5 to improve performance when a lot of cabling is run together etc. CAT 6 is designed and standardised for GigE but that doesnt mean CAT 5 won't work. 1000BASE-T[edit] 1000BASE-T capable network interface card made by Intel, which connects to the computer via PCI-X1000BASE-T (also known as IEEE 802.3ab) is a standard for gigabit Ethernet over copper wiring. Each 1000BASE-T network segment can be a maximum length of 100 meters (328 feet), and must use Category 5 cable or better (including Cat 5e and Cat 6). Autonegotiation is a requirement for using 1000BASE-T[9] according to Section 28D.5 Extensions required for Clause40 (1000BASE-T).[10] At least the clock source has to be negotiated, as one endpoint must be master and the other endpoint must be slave. In a departure from both 10BASE-T and 100BASE-TX, 1000BASE-T uses all four cable pairs for simultaneous transmission in both directions through the use of adaptive equalization and a 5-level pulse amplitude modulation (PAM-5) technique. The symbol rate is identical to that of 100BASE-TX (125 Mbaud) and the noise immunity of the 5-level signaling is also identical to that of the 3-level signaling in 100BASE-TX, since 1000BASE-T uses 4-dimensional trellis coded modulation (TCM) to achieve a 6 dB coding gain across the 4 pairs. also Category 5 vs. 5e[edit]The category 5e specification improves upon the category 5 specification by tightening some crosstalk specifications and introducing new crosstalk specifications that were not present in the original category 5 specification. The bandwidth of category 5 and 5e is the same - 100 MHz.[13][14]	dugimodo (138)
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