Dramatic performance decrease - FIXED

Thanks for the suggestions guys. Some additional troubleshooting narrowed down the problem to my PC I think.

I have two PCs capable of wired gigabit connections, and one of them writes fine (its about 16MB/sec, but that's reading off a USB drive, so I call that a win).

The one that all of a sudden is giving me problems I just upgraded the internal HD to a SSD and restored the Windows 7 image onto it. Somewhere in that process I am thinking something in the network configuration (NIC drivers or settings) is not right. I think it is using a generic nic driver, and it is not giving me a lot of options to configure. It shows as a Broadcom NetXtreme 57xx Gigabit Controller, and I only get these options:

Flow control: disabled
Priority & VLAN: Priority & VLAN enabled
Proxy ARP Offload: enable
Proxy NS Offload: enable
Speed & Duplex: auto
VLAN ID: 0

The other PC has an Intel embedded NIC and the driver give me a LOT of more options.

I am thinking some of these options are set incorrectly. I was messing with them but I have no idea what I am doing. Any ideas?

Thanks!

EDIT: I downloaded and installed the latest version of the Broadcom driver from the Broadcom site. It gave me something slightly different, but it had no effect. My options now are:

ARP Offload: enable
Flow control: Auto
NS Offload: enable
Priority & VLAN: Priority & VLAN enabled
Speed & duplex: auto
VLAN ID: 0
Wake Up-Capabilities: Both (Magic packet and wake up frame)

As additional troubleshooting steps I reinstalled the firmware and restored the NAS to defaults. I am now testing that 23 hour backup I did to see how it works :) I connected the USB drive onto the other PC and it's chugging along copying the files back to the NAS merrily at about 16MB/second. I'm pretty convinced at this point its not NAS related.