I'm using an Gigabyte GA-P35-DS3L of course i don't have a same LAN chip as you do, but my point is that when i first installed Windows 7 64bit (X64) i needed to went to BIOS to set something on my board for using it on Windows 7 64bit. You said that you installed new network driver, did you tried to enter you motherboard BIOS to see if there's any options for setting your LAN card, i mean more advanced options. Please refer to the Launch Date for market availability.It seems that you are not the only one that have that problems, a lot of people on the internet are reporting the same thing, problems with Intel 82578DC Gigabit Network Connection on Windows 7 32bit (X86) and Windows 7 64bit (X64), now my thinking is that it's not an motherboard issue, it seems to me that the only problem for that could be an operating system. Functionality, performance, and other benefits of this feature may vary depending on system configuration. Please check with the system vendor to determine if your system delivers this feature, or reference the system specifications (motherboard, processor, chipset, power supply, HDD, graphics controller, memory, BIOS, drivers, virtual machine monitor-VMM, platform software, and/or operating system) for feature compatibility. ‡ This feature may not be available on all computing systems. Refer to Datasheet for formal definitions of product properties and features. Your company as an importer and/or exporter is responsible for determining the correct classification of your transaction. Any use made of Intel classifications are without recourse to Intel and shall not be construed as a representation or warranty regarding the proper ECCN or HTS. Intel classifications are for informational purposes only and consist of Export Control Classification Numbers (ECCN) and Harmonized Tariff Schedule (HTS) numbers.
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