Old motherboard slows down internet?

[Stijn Hendriks]

So I've got a old pc with an i3 550. I dont know the full name of the motherboard so i cant give you any specifications:/
But!
When I plug my pc in with an ethernet cable for internet, it slows down the router..
Normal internet speeds are 750kb/s
But when i plug in my ethernet it slows down to 300-400kb/s
Any solutions or is the motherboard just old?
Will a new pc have the same problem (planning on building one)?

 

[Bhaumik_777]

motherboard LAN ports have speed as defined in their specs
like new ones like mine (h61m ds2) has 1000mb/s

so yes it should be cause of your motherboard but still it is not yet confirmed
try to find your motherboard, its model and name should be there on chipset.