Ethernet connection directly to switch slow, directly to router is fast

[svimes]

Might be better off in networks but as this is soho/sme I thought I would post here.

ISP with Static IP connects to Vigor 2925N Router with 5 LAN ports
Vigor 2925N Router connects to Netgear eight port switch
My Windows Server has two ports and connects directly to Router.

I have two windows XP computers and one i5 windows 7 computer connected to the switch and they are fine to access internet and our server.

I have two dell i7s on Windows 7. If they connect to the switch then accessing files on our network is very very very slow and internet access is noticeably slower. If I connect them directly to the router all is fine.

All desktop computers above specify the preferred DNS server IP addresses, which are the the ports on the Windows Server above.

Why are the Dells so fussy about connecting to the switch? What tests can I run?

Thanks

 

[svimes]

Yes both ports from windows 2008 server are connected by ethernet cable to the router directly.

Both the router and switch have up to 1 Gb ports.

 

[svimes]

Hi - the switch and the router are at 1GB.

The netgear is a GS608 V2

What I do not uderstand is why the new i5 windows 7 PC is fine on that switch but the 2 year old i7, windows 7 dells are not?

 

[svimes]

Not sure what you mean by teaming them. I simply let the router define the IP addresses apart from the server which has two reserved IP addresses using the mac addresses.

 

[svimes]

You still haven't said what speed the connection between the i7 Dells and the switch is actually being negotiated at. That's the only thing changing between everything working fine, and everything being slow.

What are the transfer speeds like between these two i7 Dells on the same switch?

Sorry how do I see what speed they are negotiating at?

I'll test the speed on the dells on the switch versus router.