Oracle Solaris 10 8/11 is the first release of Oracle Solaris 10 to support the Sun Quad Port GbE PCIe 2.0 ExpressModule, UTP. Depending on your version of Oracle Solaris 10, you might or might not need to download the updated driver.
# modinfo | grep igb 162 7b762000 1e0b8 100 1 igb (Intel 1Gb Ethernet 1.1.24)
If the version number is not 1.1.24 or later, you must install the latest driver, or you can reinstall the OS. See OS Patches and Updates.
Note - If the igb(7D) driver is not listed, the driver might not be loaded. You can use the modload(1M) command to load the driver if needed.
# modload /kernel/drv/arch/igb
where arch is amd64 for 64-bit Intel systems or sparcv9 for Oracle SPARC systems.