Soyo SY-6KD LX Dual Pentium II Board

The Good

Looking at the Soyo SY-6KD, you quickly pick up on one major feature, the presence of not just one, but two Slots for Pentium II processors.  The Soyo SY-6KD is Soyo's flagship Dual Processor Pentium II LX motherboard, sporting 4 DIMM slots, 5 PCI slots (1 can be used for an I20 Upgrade), and 2 ISA slots, the 6KD means business.  Expansion is critical in the high end workstation/server market, and Soyo meets the heavy demands of the market by outfitting the 6KD with just about everything mechanically possible, one would expect a kitchen sink to pop out of the board at any time...you never know with a product as well rounded as this motherboard. 

A large board itself, the 6KD has good reason to measure in at 24.5 cm x 30.5 cm in an ATX form factor, the addition of the Second Processor Slot, not to mention the recently unheard of amount of PCI slots make the 6KD 747-square centimeters of quality, performance, stability, and reliability.  Packaged with the motherboard is a "One-Page Installation Manual" as well as the standard packaging found with just about all Pentium II motherboards, with the addition of the unique Slot-1 Terminator card for users that will be making use of only one of the two processor slots.

If you plan on running the 6KD in a single processor configuration the Pentium II you plan on using must be placed in the Slot closest to the stacked ATX I/O ports, occupying the second slot will be the RAM-like Terminator Card Soyo provides with the motherboard.  Failing to install this card will result in a system that fails to boot, it's as simple as that.  Running a dual processor system is a bit different from running a single processor system, you can't just install a second processor and expect double the performance.  You must take into account a few considerations.  First of all, technically, two processors running in any one system must be of the same stepping, revision, and clock speed in order for you to get the maximum performance/reliability out of your system.  Not to say that running two different processors in the same system won't work.  For the purpose of putting an end to the curiosity testing a Dual Processor board will produce, a Pentium II - 333 was first installed in the SY-6KD.  A quick trip into the AMI BIOS Setup (which amazingly enough looks MUCH like the conventional Award BIOS Setup...), under the Chipset Features, reveals Soyo's Sofset Jumperless CPU Configuration helps tremendously with the hassles of capping virtually inaccessible jumpers.  Selecting the 333MHz Setting out of a list including 233MHz, 266MHz, 300MHz, and 333MHz and after saving the settings/powering down the test system a second processor was installed in the system, not another Pentium II - 333, but the next closest thing, a Pentium II - 350.  Since the Pentium II - 333 and the 350 both support the 5.0x clock multiplier, it made sense to use those two in the board together.  There have been reports of Windows NT 4.0 taking a dramatic performance hit when detecting Multiple Processors that aren't of the same stepping/revision, which happens to be a downside to using two processors of different clock speeds, steppings/revisions.  The actual performance hit will be discussed in the Multiprocessor Systems article @ Anand Tech.

Upon firing up the test system, the BIOS reported 2 x Pentium II - 333 Processors, and Windows 95 booted perfectly fine.  This brings us to the next point when dealing with Dual Processor Systems, in order for one to achieve a performance increase by using two processors vs a single processor, you MUST have Operating System Support.  Windows 95, for example, will NOT make use of the Second Processor, rendering a Dual Processor System under Windows 95 a waste of money.   The only Microsoft Operating System that does support multi-processor configurations is Windows NT 4.0, and even then under NT 4.0 you won't see much of a performance increase (if any) unless you run Multi-Threaded Applications, or applications that are designed to take advantage of multiple processors.  With that set aside, let's discuss some of the advantages to running a dual processor system.  Under a supported OS (NT4, BeOS, Unix, Linux, etc...) adding a second processor to your system can increase performance by as much as 30% in some cases, unfortunately that number isn't consistent in all cases.

As a normal Pentium II - LX motherboard, the Soyo SY-6KD definitely cuts it, performance-wise the board remains competitive although does illustrate a need for improvement.  Like much of its competition, the 6KD offers a BIOS Monitoring System for Processor Voltage (both processors) as well as Temperature if you opt to use the two 3-pin CPU Fan connectors provided on the motherboard itself, one for each processor. 

The Bad

The Sofset Jumperless CPU Configuration Utility resembles the ABIT SoftMenu^TM wanna-be's in the market today, one of its major short-comings is the fact that it doesn't offer a User Definable option, the only way to overclock this motherboard is using the pre-defined settings, or the Turbo (75MHz Bus Option)...even then, the highest possible clock speed is 375MHz, provided you have a CPU that supports the 5.0x clock multiplier (5.0 x 75 = 375MHz).  For a dual processor motherboard, the SY-6KD isn't quite competitive, as a single-processor board it does shake the competition quite a bit in terms of expandability.

An improvement in documentation (the "one-page manual" doesn't cut it) would have been a plus, unfortunately you can't have everything.

BIOS Settings

Recommended SDRAM

Recommended SDRAM: Advanced Megatrends SDRAM; Corsair PC100 SDRAM
SDRAM Tested: 1 x 64MB Advanced Megatrends SDRAM DIMMs; 1 x 64MB Corsair PC100 SDRAM

Manufacturer: Advanced Megatrends
Purchase Web-Site: http://www.megacom.com

Manufacturer: Corsair Microsystems
Purchase Web-Site: http://www.nf-ny.com