ICH5 or Silicon Image?

My motherboard has the i875p. So it has the ICH5, I think that's what it's called. That has two S-ATA channels on it.

Although the board also has a Silicon Image controller too, and that has 4 more S-ATA channels on it. The Silicon Image controller is the same size as ICH5 or larger.

what are the differences between them?

As of now I have a Raptor that uses S-ATA, and a DVD/CDRW that uses S-ATA also. Then I have a normal P-ATA 250gb that will be going on IDE1.

So which one do you think is better? Should I put the Raptor on one and the DVD on another?

silicon image is basically a pci device. the Intel one is built directly into the chipset and bypasses the PCI bus so it should be faster.

The southbridge has native support for two SATAs, and they should be used first. The only RAID-mode supported by this controller is RAID 0.

The Silicon Image controller is PCI-integrated, which means that the devices would have to compete for the same bandwidth (133 MB/s) as any other PCI-device. This controller supports both RAID 0 and 1.

You should use the two built-in connectors. However if you're not using any PCI devices (controllers, soundcard, etc), the additional SI controller shouldn't cause much of a performance hit. If you want to use more hard drives in the future, the SI-controller would come in handy. As you probably know the LAN-controller is not linked to the PCI bus on your mobo, so under normal circumstances the PCI-bus shouldn't become a bottleneck.

I wasn't thinking about how the SI one is connected. I only have a modem and sound card on the PCI bus, so putting the DVDrom on there wouldn't be bad, but I'm putting everything on the ICH5.

It supports RAID 0 and 1, along with combonations of them. I dont use RAID so I didn't look carefully.

Turn off the Sil controller in BIOS and save some resources

Ive found the Intel ICH5 (or ICH5R for raid) to be better than the SI chipset ( IMO) .

Go with the Intel