Connectivity problems: Unidentified Network

Okay, a little bit of background:
I formatted my PC just yesterday and installed a clean copy of windows 7 Ultimate x64.
Installation went smoothly and everything was okay.
Then today I had to restart my router and since than I keep having problems with my ethernet connection

Every time I plug in the eth cable, the system will start recognizing the connection and then will give me the unidentified network status

Only a few times I've been able to get a connected status, with a handful of packets sent and received but the packets stream would still end before I could load google.com page (which is one of the lighter ones I could have tried)

Every other time I tried to connect, I would have had some sent packets and none received and from time to time i would have had no default gateway at all..
Router configuration's okay, cuz all of the other 2 computers I have in my house can connect and I'm using the very same eth cable on my laptop to write this message right now, having no problems at all and no unidentified network status...

Any help would be mostly appreciated, feel free to ask for the result of ipconfig or of any other diagnostic tool.
-Alecossy

I assembled my pc by buying all of the parts like 5 years ago so it doesn't have any proper manufacturer...
Mainboard is an ASROCK mounting an nvidia Nforce network controller.
I tried to look for that network controller updated drivers but I wasn't able to find it...
I'd like to add that I have used the PC for 5 years straight now and never had a problem with it...

Will do as soon as I get back home... (that should be in like 8 hours or something...)
Will then tell u what happens...

I'd like to ask if you simply restarted your router or actually reset it to factory defaults?

A possible reason I can think of is that your onboard LAN and the router can't negotiate a connection using the same line speed (10, 100 or 1000 Mbit/sec) and/or a duplex mode (half or full).

This isn't related to TCP/IP or DHCP, it's the very first thing two Ethernet devices have to establish and agree on before any data can be passed back and forth (and successfully received on the other end) across the cable link.

It may be worth a try going to your network adapter in Device Manager, opening its properties and looking in the Advanced settings to see whether line negotiation is set to "auto". If it already is, try each of the manual options to see if that makes any difference.

Sp1 was already installed and Asrock website only gives out video and audio drivers for its mainboards...
Corazon, tried each of the options, none of them worked...
Strange thing is that sometimes I get the "internet access" icon but whenever I try to load a page it would not load...

I don't have any antivirus (the system is just freshly installed, I would have needed an internet connection to download anything) and I don't have a wireless adapter to put in (all of my PCs are connected through wired ethernet connection, the only wireless one is the Laptop, which has an integrated wireless card).
The network adapter figures as NVIDIA nForce Networking Controller...
Checking your link just now...