Here's the IO you need for high end mainboards

TOP NOTCH mainboards are not cheap, with $500 a piece not too far from the most expensive offerings - especially if the mainboard happens to use the Extremely Expensive Nvidia 680i chipset, which can easily amount to close to a half of the total board cost.

Of course, if a given mainboard enables you to achieve, say, 20% extra performance out of a system costing a total of $5,000, then the extra $100 for a good board equates two per cent of system cost for 20% of performance. That sounds like a good deal to me.

However, overclocking performance benefits in practice can't be easily quantified inside the brochures. So, to differentiate themselves, the boards have to rely on the feature sets.

Now, look at a typical high end mainboard like, say, Asus Striker Extreme or MSI P35 Platinum - the list of features alone, in either case, would fill in two printed pages. How many of these does a high end user really need, and are there some capabilities still sorely missing? Let's go through my list:

Eight S-ATA ports: the 0.1% or so of users who actually make a five-disk RAID5 array, plus have a S-ATA optical drive, yet also envision using up to a pair of external eSATA data transfer disks or flash sticks, would be happy with this feature. Otherwise, in the remaining vast majority will not have a need for more than, say, four - but anyway, S-ATA ports are small and cheap to implement, so why not have a few more for some RAID play, especially if the next generation of South Bridge chips incorporates hardware XOR for less CPU utilisation in RAID5 processing. At least one legacy P-ATA port is stil to be kept for another year, at least - but not the floppy connector. Once XP is less prominent, the floppy drive will not be needed even for the installation drivers, Vista does away with FDD requirement for this.

Right now, two eSATA ports are fine - in the next year or two, eSATA will complement, maybe even replace, USB as the preferred - faster, less CPU usage or driver headache - external flash storage medium. Two ports with decent space in between them should take care of both external HDD and thick flash memory devices.

A dozen USB ports - OK, there is no need for more than eight to 10 as long as there's flexibility in apportioning the front-panel and back number, and, just like the eSATA above, at least few of the stacked back panel connectors have wider spacing in between them to allow fitting of thick USB memory sticks in parallel. Wide spaced USB connectors are more important then a sheer number of the ports if half of those are blocked by large sticks.

Firewire - I'd personally like to have 1394b Firewire800 back again, if not for Mac stuff then for the sheer speed of the interface for professional multimedia devices. One 1394b plus two standard 1394a Firewire400 pieces are more than good enough. And yes, if you happen to land one of the upcoming OCZ Firewire memory sticks, don't be surprised to see that it is faster and less CPU-hogging than its USB equivalents, despite the theoretical USB 2.0 bandwidth advantage. So, keep the Fire burning on the Wire.

That's definitely not the case with so-called "software HD Audio". As said many times, for the high end board, you got two plausible on-board sound choices. One is proper DSP-based, hardware accelerated sound - Creative EMU20K2 PCI-Express X-Fi with X-RAM, or Asus Xonar D2X on-board equivalent, either of them with a well shielded audio output riser card. The other alternative is - no sound at all. On a, say, US$ 5K high-end gaming or multimedia machine, why should the user bog down up to 10% of total CPU cycles and suffer reduced audio quality just to save, what, US$ 50? A measly 1% of the total system cost would make so much difference in the total listening (not to mention recording) experience, beyond of course some gaming frame rate gain from those freed CPU cycles.

If no on board sound, the freed mainboard real estate, no matter how small it looks, is still something on crammed current products. It can be used for more important things, like say two extra system fan power points (at least 6, preferably 8, fan on board power points are desirable) or maybe, an extra +12V 4-pin power input to feed extra GPU or CPU VRMs, also restoring of old (but sometimes still very useful!) serial and parallel ports at the I/O shield panel - or just another PCI-E x1 slot, now that you can plug things like Robson TurboMemory, SSD storage or physics cards in there.

Talking about PCI-E slots and their newfound use, I feel that at least two unobstructed PCI-E x1 slots should be available even after mounting two GPUs in SLI or CrossFire on the x16 slots. On top of it, two (no more, no less) old 32-bit PCI slots should be there. No less than 2, because you might stand a chance of requiring that many for an odd I/O card, and no more than 2 because, even if you get an extra on-board PCI device load, you can still push the PCI bus reliably to 40 or even 50 MHz clock from the usual 33 MHz base with this many loads - any more loads and that might not be doable. Anyone using a pair of fast UltraSCSI drives or running an X-Fi or physics card on that PCI will appreciate the extra bandwidth boost. So, easy BIOS setting for the above would be recommended.

What about the big slots for graphics? Well, at present, the optimum is dual x16 slots for the GPUs and one x8 slot for the physics or GPGPU or 3rd SLI / CrossFire card. Of course, an additional x8 slot using x16 electricals would also be welcome if you really want to try Quad SLI or CrossFire. Most likely though, that slot won't be used in 99% of the cases. If, of course, you have Intel X38 or Nvidia's next Nforce, both with PCI-E v2 double speed signalling, even better for you. In either case, lower insertion force slots would be most welcome, so that the board is not broken trying to insert a 2 pounder GPU (or two) in there.

What I do not encourage on the very top end of boards are the 'compromise' 2 x8 slot solutions for SLI or CrossFire. Again, if you pay through your nose for the fastest quad core CPU, dual GPU, a load of expensive memory and so on, all that to obtain the very best performance, why cripple it with half-width slots then? Yes, the difference may not be that much often, but it is still an unwelcome speed reduction, something not usually acceptable to "enthusiasts" shelling out top dosh for pure maximum performance, and then spending weeks "tuning" it for some more. So, for P35 chipset, where it is x16 + x4 or, sometimes, 2 x8, my suggestion is a single GPU and optional physics config in the first setup. Forget about 2 x8 - if you need CrossFire, wait a month and get X38-based board. If you want SLI, well NF 680i is all over, heat or no heat.

Embedded power, reset and CMOS clear buttons on board, replicating the connector function - good idea, and keep it that way. Really useful for early tabletop board tests and tuning. Even better so if there is a status display of some kind on or connected to the board, telling us the phases at which the system boots (or dies). For the connectors to front panel power, reset etc buttons, the location as in Nforce boards should be considered, right on the centre of the board near the 24-pin power connectors.

Dual Gigabit Ethernet, hopefully with accelerated TCP/IP stack handling through the South Bridge or network chips, is a standard now, and nothing less should be accepted on a high end board. You may see some new mainboard, like Asus P5K series, having 802.11b/g or similar wireless included - personally, I'd wait for "final standard version" 802.11n point interfaced via PCI-E to put on my board, for some future-proofing.

Finally, for this round, vendors shouldn't stinge on providing proper multi-interface USB/Firewire, even eSATA, interface adapter boxes that fit in front, right into the 3.5-inch floppy bay, now rarely used as the floppies are mostly gone. And, when at that, how about bundling in one or two eSATA cables in the package?

Next, in the final part, we talk about performance features and enhancements, and possible returns out of those. µ

See Also
High end mainboards need special features Part One