Details on the Chipsets - 570 Ultra and 550
Now we get into the lower specs of the nForce 500 family aimed at the entry and value level computers, the nForce 570 Ultra and nForce 550. nForce 570 Ultra we have partly covered in our 570SLI, it supports the same features but lacks SLI support. Its additional features such as audio, GBE and SATA configs are identical to the 570SLI and 590SLI but you won't be able to run SLI dual graphics.
The nForce 550 is the only chipset to have major changes. 550 is aimed at entry level computers based around the Sempron AM2 series, but works just fine with FX and X2's, as we tested. nForce 550 is a single chipset solution from nVidia with all the features integrated into the 550MCP. There is a single PCI Express x16 lane for a graphics card. Like the 570 Ultra, it does not support SLI configuration, so any hopes of budget SLI go right out the window here. It has the same four PCI Express lanes left for additional PCI-E devices.
What has changed are the SATA and GBE configs. Only four SATA ports are supported on this chipset with two IDE ports. Media Shield is still present so you can combine SATA and IDE drives into a RAID array.
Gigabit LAN is still supported on the NF550 but you don't get two ports. This is still more than acceptable, as some of the NF4 chipsets in the value range didn't come with Gigabit LAN and its good to see this added.
Lastly is the HD Audio. nVidia could have stripped the 550 down to using AC'97 audio or its value chip, but its very nice to see that they elected not to do that here.