Netgeare GS605 - Computer Crawls When Connected To Switch But Not Router

I just upgraded to GS605 Netgear gigabyte switches on my network, and I use Cat 5e cables, so I can use the gigabit Ethernet.

One of my Windows PCs seems to have a very slow connection. I see an active 1K link on the switch for this port, and Windows reports that the link is running at 1 Gbps, but the computer takes 3-5 minutes to load Amazon.com and has ping times on the order of 700 ms.

I have another Windows 8 PC that works perfectly fine, and I have a Mac mini which is also connected to the switch and works fine.

If I take the Ethernet cable from the messed up computer and connect it directly to the router (not the switch), it is fast again. However, connected to the router, I'm back to 100 Mbps speeds, not gigabit speeds.ipconfig gives the following output:

-Hostname: my computer's hostname
-Node type: hybrid
-IP routing enabled: no
-WINS proxy enabled: no
-IP address: my computer's DHCP address
-MAC address: my computer's MAC address
-Default gateway: my router's IP
-DHCP server address: my router's address
-IPv6 address: something long (I'm not familiar with IPv6 addresses)
-Various tunneling adapters, which are all disabled

I have had other computers in the same port on the switch and they all work fine. I also plugged this computer into a different port and had the same problem. Netgear tech support wasn't useful.I actually have another switch of the same model, but when I replaced this one with that one, it had the same problem.

I confirmed gigabit speeds between two other computers, both connected to this switch, so it does work at those speeds. Those computers also have fast Internet.I don't have any clones MAC addresses in my network, and as for logs.... the only place I can think is the log file from the router. I didn't even think of that, the only other place would be event viewer within windows.This computer dual boots Windows 7 and Windows 8, and has these issues in both OSes.