Community
cancel
Showing results for 
Search instead for 
Did you mean: 
idata
Community Manager
1,739 Views

link speed reduced while in sleep mode

Hello all,

Every time i enter to sleep mode in any of computer on my site the link speed is automatically changed to 10half (instead of 100full). most of my ethernet cards are intel 1000 pro. I have tried to install the latest drivers about a week ago (downloaded from intel's website). This has added me some checkboxes at the "power management" Tab of the ethernet card. on of them was something like "Reduce link speed while in stand by". I tried to check it. to uncheck it. to check all of them. to uncheck all of them. it didnt matter. no matter what i tried, every time i go into sleep mode (or stand by. its the same) the link speed is reduced.

Is there any way to prevent it from happening ??

Thanks.

0 Kudos
6 Replies
Patrick_K_Intel1
Employee
100 Views

I am assuming the problem is that when it comes out of sleep mode the link speed stays at 10Mbps half duplex, is that correct?

There MAY be a BIOS option for this as well.

You might also try setting the line speed in the driver to 1000Mbps Full Duplex, rather than auto-negotiate.

idata
Community Manager
100 Views

No, when sleep mode is over everything is back normal. The problem is that the moment I enter sleep mode the link speed is reduced to 10half. I want the link not to change at all, even for a little while.

Patrick_K_Intel1
Employee
100 Views

That is what it is supposed to do :-) It's to save energy.

I am pretty sure that per the PCIe specification, when the device goes into low power mode it MUST reduce speed and save power.

Just curios - why would you care if it was 10Mbps and half duplex when it is in sleep mode vs 1000Mbps Full Duplex.

idata
Community Manager
100 Views

I have a security system over my network, and when a link changes then it tries to re-authenticates with the computer. but because it is on sleep mode, there is no active operating system to talk to, so the authentication fails and it really make a mess on my net.

So, no chance of forcing the adapter not to change his link speed?

Patrick_K_Intel1
Employee
100 Views

Again - not my area so take my thoughts with that in mind.

Can you maybe change the settings on the switch to only support 1000Mbps, and not auto-negotiate?

I believe that per the PCIe spec we will try to re-negotiate to a slower speed, but if the link parter will only link at 1000Mbps, we shoud link at that speed.

Thinking about it more, you may still have issues, as when the controller tries to go into saving mode and re-nogotiate the speed, even if it negotiates it back to 1000Mbps, the link is still lost during the negotation, and your problem (as I understand it) will still exist.

idata
Community Manager
100 Views

Hi, I would like to know how you verify the link speed in sleep mode. Please teach me. Thanks!

Reply