A most curious problem

[George Powell]

I'm getting a rather interesting problem which has baffled me so far.

My PC is connected onto my home network - gigabit wired using the onboard network adapter of my ASUS Z77 Sabertooth.

Normal operation is fine, however in certain circumstances when the computer goes into a power save state it can't be recovered by moving the mouse or tapping the keyboard.

This is annoying but not a deal breaker - however when this happens it also has the effect of inhibiting wired communication over the whole home network.

Resetting the PC immediately restores things to their previous state.

Does anyone have any ideas as to what might be happening?

I've gone through numerous BIOS updates and all the drivers for the motherboard etc are fully up to date. The problem has manifested itself fairly consistently through all these changes.

 

[drebo]

Turn off Wake On LAN in bios. More specifically, if you can, disable IPv6 support for WoL.

There's a defect in a certain NIC chipset that causes it to spew billions of multicast packets in its sleep state. IIRC, they're simple neighbor discovery packets, but the quantity of them is what's breaking your shit.

 

[George Powell]

I'll look into that - thanks.

 

[mikeymikec]

This is annoying but not a deal breaker - however when this happens it also has the effect of inhibiting wired communication over the whole home network.

I'm not 100% sure what you mean by this. The previous para said that the computer won't resume from (presumably) S3, then the one after the quoted para said that you reset it to correct the issue, so at what point is wired communication affected?

I'll assume for now that the computer does kind of resume from S3 but it doesn't work properly (networking doesn't work?), if so I'd go into Device Manager and try changing the "Power Management" tab's option for the NIC that tells the PC that it can switch off the NIC to save power. I saw an issue like this in my first AM3 builds that ended up getting properly corrected with a NIC driver update.

 

[George Powell]

The computer does not resume from sleep at all - the only way round this is to hard reset.

While it's in this state the wired network is not available for all other devices on it - any other PC, my NAS, my TV etc.

Disabling IPv6 and WOL has unfortunately made no difference so far.

 

[mikeymikec]

Do you have a spare PSU to try? Resuming issues are sometimes PSU related.