I have the exact same problem with my DX58SO. After sleep, the network adapter reports "cable disconnected" and if I disable/reenable it disappears from the list of adapters in "Control Panel\Network and Internet\Network Connections". After rebooting all works fine again.
OS: Windows 7 Ultimate 64 bit
I believe this question is about the same problem: http://communities.intel.com/message/93877#93877
I have the same damn problem with this board, tried the latest BIOS and drivers but no luck
Will try the 5200 BIOS ti see if it really fixes the Issue
Here is a copy of the email I got from Intel Technical Support. I actually fixed the problem before I got the email. Downgrading the bios fixed the problem for me.
Thank you for contacting Intel Customer Support.
I understand the LAN adapter turns off after the system comes back from sleep mode on Windows 7*.
In this case, we will recommend you testing the system with BIOS version 5200. Please perform a BIOS recovery to do the update. The file can be found at: http://downloadcenter.intel.com/Detail_Desc.aspx?agr=Y&DwnldID=18938&ProdId=3018&lang=eng
For BIOS recovery instructions, please refer to: http://www.intel.com/support/motherboards/desktop/sb/CS-023360.htm
If the issue persists after using BIOS version 5200, please try using the LAN driver version 14.6. You can find this driver at:
Message was edited by: Apota