Lower download speed through gigabit switch

[davej99]

I noticed today my download speed on a max sync of 8.128Mbps was not its usual max of 6.800, but around 0.12. Using BT Beta speed tester. Regular BT tester failed. I connect using all cable, 1Gb PC NIC, Gb switch, 100Mb DGN2200 router. After a full reboot of everything and after removing Gb switch, the download speed was initially erratic, but then recover to the max. Purpose of Gb switch is to connect PC and NAS at Gb. Seemed like there was a possible BT or session problem.

Reintroduced the Gb switch and this reduced the speed to 3.6-4.6, about half max. Reconnecting directly to the router restored max speed. After setting the PC NIC to 100Mbps full duplex, I got max speed both thru the switch and directly to the router.

So switch connected to router at 100Mb and PC at 100Mb is OK. Switch connected to router at 100Gb and PC at 1Gb is not OK. PC connected to router at 100Mb, auto or forced, is OK. Have not checked performance of PC-switch-NAS Gb yet.

Any ideas?

Thanks, Dave