I have a HP Touchsmart TM2 2105 laptop, quite recently bought. The NIC is Gigabit speed capable, with a Realtek R8168 chipset.
I installed the drivers from Realtek, it works,
ethtools indicates 1000Mpbs. But a simple download test with a Windows PC shows a maximum speed of 130 Mbits. The same test, with the same hardware, but with the laptop under Windows (on another partition) shows approximately 500 Mbps.
I don't know what to do?
The other machine and the switch are gigabit capable, since, the download test with the same machines but under Windows gives approximately 500 Mbps.
I will try MTU and let you know.
If I test under Linux with the command
iperf, I get app 650 Mbps!
edit : with MTU= 9000 -> no difference :(