Help!

Hi, I'm going to do a massive upgrade for my computer, pretty much building it from scratch as I'm going to replace my video card, my CPU, my power supply and my motherboard.

I've decided on the MSI Radeon 4850 for the video card,
Corsair 620HX for the power,
Intel E8400 for the CPU,

but I haven't decided what motherboard I should get. I have limited knowledge in compatibility. I may want these products, but are they compatible? What motherboard should I get that would not only be compatible with these products, but a very good buy? Any assistance would be most welcome.

Important fact: This is for a GAMING computer, just to keep that in mind.

ACPI Uniprocessor PC
WDC WD50 00KS-00MNB0 SCSI Disk Device
LITE-ON DVDRW SHW-160P6S
Linksys Wireless-N PCI Adapter WMP300N
AMD Athlon 64 Processor 3200+
1.5G RAM

My total budget is around $700-800 to buy the aforementioned components (vid card, CPU, power, motherboard). I want to use the components I've already listed in my original post.

Okay, cool, thanks! I do have another question. See, I have an SCSI 500gb hard drive (wdc wd50 00ks-00mnb0 scsi to be precise) and I know most motherboards nowadays use SATA (I believe?). Is my hard drive incompatible? If so, is there any way around this without having to buy a new hard drive as well? Any suggestions?