Sign in with
Sign up | Sign in
Your question
Solved

PCI-E x1 Bandwidth Question

Last response: in Motherboards
Share
September 13, 2012 3:53:21 AM

Hello,

I've got a quick question for the community here. I'm going to be adding two PCI-E 2.0 x1 cards to my system, one for SATA III and another for USB 3.0. I'm wondering if each PCI-E x1 slot will have the full bandwith available to it, or if it's split between all the PCI slots on the system?

For example if I'm running an SSD off one adapter card, and USB 3.0 hard drives off the other will I get full bandwidth or will each device added to the PCI-E bus cut down the bandwidth of the others?

More about : pci bandwidth question

a b V Motherboard
September 13, 2012 4:07:22 AM

This all depends on how your motherboard is wired. It should make these details clear in the documentation. One thing I would note is that a SATA III controller is definitely going to bottlenecked by PCI-E 2.0 x1 (which is why most of the integrated Marvell controllers have a bad rap for performance issues).
September 13, 2012 4:41:14 AM

Thanks for the response! I realized SATA III would be bottlenecked by the PCI-E, but still faster than SATA II on the motherboard (although about 100mb/s slower than regular SATA III, from my understanding at least). This might seem like a daft question (because it probably is) but what should I be looking for in the motherboard manual that describes how the PCI bus works on my system?
Related resources
a c 431 V Motherboard
September 13, 2012 4:51:24 AM

how the pci slot are devied. if it a 32 lane pci mb. look t osee if the video card is 16x or 8x. then what other devices are using the pci lanes. most mb have a cheat sheet in front for that. (have the usb..network..sata connected to the pci lanes).
September 13, 2012 6:11:41 AM

Okay I looked up my North Bridge (it's the AMD 770 model). According to Wikipedia: "One physical PCIe 2.0 x16 slot, one PCIe 2.0 x4 slot and two PCIe 2.0 x1 slots, the chipset provides a total of 22 PCIe 2.0 lanes and 4 PCIe 1.1 for A-Link Express II solely in the Northbridge" My Motherboard has one PCIe 2.0 x16 slot, and two of the PCIe 2.0 x1 slots. So I guess I'm still a little unclear as to exactly what that means for bandwidth?

Best solution

a c 431 V Motherboard
September 13, 2012 6:28:42 AM
Share

you have two slot running at 1x bandwith.
September 13, 2012 8:57:51 PM

And 1x bandwidth is 5Gbps/500mb/s correct? Meaning that each slot wouldhave 5Gbps bandwidth?
!