Hi there,

I recently bought a new computer with a asus rampage extreme motherboard.
It features Intel X48 chipset and comes with 2 black sata ports called speeding hdd.
The two ports are driven by a Silicon Image SIL5723 controller.
I believe it sets up both drives in raid (some sort of round-robin) mode and makes it access able as a standard ATA interface.
I've connected two 1TB Samsung Spinpoint drives to it, and I had no trouble installing Fedora 10 x86_64 and Windows XP x64.

However when I try to install either iPC or iDeneb they wont be able to access any of my partitions.
It find my speeding hdd though and it lists my partitions but a timeout occurs when I try to format my FAT32 partition (intended for OSX).

I think there are other drivers interfering.
Here are two screenshots of the install screen:

I dont know that board but if it doesnt need no drivers to be recognized its probably some sort of SATA port multiplier.
Looking at the screen it looks like your boot disk its using IDE mode (ApplePIIXATA driver), port multiplying normally requires AHCI mode to work.
You can change it in the board BIOS , but if you have multiple SATA controllers you will need to change the one that the Silicon Image ports are connected to, normally the secondary controller but it depends on the board (the motherboard manual should say something).
Also notice that changing from IDE to AHCI mode would stop XP from booting with fatal STOP error, you would need to reinstall it (and for that you would need a diskette drive or a custom XP CD with AHCI drivers integrated) or do some registry editing (before doing the IDE to AHCI) to allow it to boot. OTOH most Linux distros should change from IDE to AHCI gracefully.