Has anybody noticed that the dual Gb LAN RTL8110SC/RTL8110SC is on the PCI bus? The following NTttcp ethernet throughput test shows that RTL8110SC is 35% to 40% slower than a PCI Express Gb LAN such as Marvell 88E8056 or Realtek RTL8111B:



with higher CPU usage:



Source: PROHARDVER! - Alaplapok Core 2 Duo ala - 2. resz - Nyomtatobarat verzio (January 2, 2007). Typos in these charts:

  • "Asus P5B Dlx (Marvell 88E8801)" should be "Asus P5B Dlx (Marvell 88E8001)". 88E8001 is a PCI Gb LAN.
  • "ECS PX1 (RTL 8139)" should be "ECS PX1 (RTL8110S)". RTL8110S is a PCI Gb LAN, a variant of RTL8110SC.

Another NTttcp test shows a similar result: ComputerBase - Test: Asus P5K Deluxe WiFi Edition (May 21, 2007)

Another test in The Tech Report - Intel's P35 Express chipset (May 21, 2007) also shows that the PCI Gb LAN 88E8001 is much slower than other PCI Express Gb LANs, though it does not include RTL8110SC.

Abit uses this crappy PCI Gb LAN solution in AB9 QuadGT too. There are only 6 PCI Express lanes in the southbridge. In these motherboards, the lanes are assigned as follows:

  • 4: PCI Express x16 slot at x4
  • 1: PCI Express x1 slot
  • 1: IDE controller

while in ASUS P5B/P5K series motherboards with two PCI Express x16 slots,

  • 4: shared by the PCI Express x16 slot at x4 and the PCI Express x1 slot (x4 is automatically slowed down to x2 when x1 is used)
  • 1: IDE controller
  • 1: PCI Express Gb LAN