Some insights, and addressing some misnomers ...
RAM:
For the Socket 1366 mobo I'd look at the DDR3 1600 as a minimum
DRAM timing is more important than synchronized clock. Who cares if it's DDR3 1600 if it's going to take longer to fetch than a similarly priced DDR3 1333 memory set. I've seen this too many times, a lot of vendors pushing high synchronized clocks, and the timing is horrendously slow.
Remember, DRAM access times are very slow themselves, only about 40-50MHz (20-25ns). Synchronized clocks are only good for burst operations. That's why the timing numbers are so high, those are the cycles the system has to wait. The worse those numbers are, the worse it gets.
Also, I've seen a lot of manufacturers quote timing number for a
slower clock, and then advertise with a higher clock. So the timing is far worse at the higher clock, let alone may not work at the stock 1.5V voltage for DDR3.
Video:
DVI or HDMI only and I'd make sure the card I got was SLI. I'd get one that interfaced with either PCI Express 2.0 x16 or PCI Express 2.1 x16
It's fine to buy a card with SLI, but I haven't used SLI myself (sans back in the old Voodoo2 days). The funny thing about SLI is that for lower-end SLI cards, you can typically buy a single card that is faster for the same, or less money, let alone power. And for the highest-end SLI card, it gets really expensive and power hungry, and might be better just to wait a year.
Power Supply:
Minimum 700W or higher. If you are planning on running dual SLI video cards then I suggest getting in the 900W realm.
Assuming one is going SLI.
CD / DVD Burners:
Stick with the SATA drives only. Not only are they faster than the IDE type
This is a falicy. Parallel ATAPI drives aren't any slower than Serial ATAPI drives. In fact, many Serial ATAPI drives are still actually Parallel ATAPI drives with an ATA-6 to SATA-150 bridge inside, because of old stock. Only SATA-300 ATAPI drives are native, and even then, an optical ATAPI drive is still much, much slower than even old parallel buses.
but the IDE is old technology
Parallel and Serial ATA are the
exact same technology above the PHY-level. Only the PHY changes, and how the ASIC works. Granted, most newer ATA technologies (NCQ, etc...) haven't been put into parallel ATA, but most of those aren't found in even SATA-300 optical ATAPI drives either. So whether its Parallel or Serial ATAPI, they are virtually the exact same performance when it comes to optical ATAPI.
and you have to deal with thos wide ass ribbon cables. Whereas the SATA cables are significantly thinner which helps your air flow inside the computer. This in turns in helping you keep your system cooler which gives your system longer life.
SATA cabling can have it's own issues, including breaking the connector. Some vendors have learned from this. Others have not. The key is to find a vendor who has good cables that lock around a post, and devices that offer a good post. I wouldn't mention this except I've lost connectors as a result of shipping, and I've seen PC OEMs have theirs trashed in shipment as well (even when support-glued well).
The main thing SATA often offers over ATA is that most ATA is connected to a legacy LPC ASIC, so it shares the same bus as all other legacy LPC components. Most SATA controllers are connected to either a PCIe channel or two or four (Intel) or directly on the systems HyperTransport interconnect (AMD). But in the case of ATAPI, it's so slow, it really doesn't make that much difference. Hard drives are another story.
With that all said, I still buy SATA ATAPI devices, because they are no additional cost. The LG SuperMulti's do everything, and cost $20. They even have the new LG BluRay/HD DVD + SuperMultis that are under $100.
Fan/Heatsink:
Needed to cool your processor. I personally like the direct cooling where the fan points directly to the processor but they do offer indirect cooling as well.
The BTX form-factor actually addressed this, as well as "flipping" the orientation of the mainboard so the cards are "upward," improving cooling. Unfortunately BTX became PC OEM-only, as consumers wouldn't accept it.
I like "flipped" ATX designs where they do the same. Not quite as good as BTX (CPU cooling is better, the GPU is the "top card"), but they help in this regard. But most of them are costly. Of course, if you're dropping $800 on a pair of highest-end SLI video cards, might be worth it.
Hard Drive:
Western Digital, Seagate or even Hitachi. Stay away from Maxtor drives, they are typically pieces of junk.
Maxtor = Seagate!!!
This is why
brand name means shit. You have to take it on a specific model (and even sub-lot) basis. Hit reviews and then check back. Do you know how many times different vendors fab for others? Same deal in the mainboard world too.
The drives come in different interface styles. IDE, SATA, SAS and SCSI. Whatever your choice stay away from the old IDE interface. Again it's slow and outdated.
It's not slow, ATA drives are just starting to hit the limits of ATA-6/133MBps. The bigger issue is how the ATA controllers are often implemented on systems, connected to the legacy LPC. SATA is better because it is often a dedicated channel. SATA also offers NCQ and other things that could be implemented in ATA, but are rarely.
I haven't seen a SATA-150 in a long time, so no need to worry about those. They were almost always a ATA-6/133MBps ATA drive with a SATA-150 bridge. Everything today should be native SATA-300. A few are pushing SATA-600, but that requires twisted pair cabling (which the vendor doesn't tell you about).
SAS is just SATA, with SCSI-2 protocol added (and backward compatible with SATA, long story). Most SAS drives are typically implemented in 2.5" at 15Krpm, some 10Krpm. SCSI ... haven't done that in 5 years, not with SAS around. The only advantage to SAS is that it was designed for external, 27' cabling and has strict standards. eSATA is a hack (not in the original spec) with different, non-standards and doesn't go much beyond 5', if it works (been there, failed that).
