Ask any Pentium Pro user if they would've shelled out the cash for their system a few years back knowing that the Socket-8 Pentium Pro interface would pretty much be a dead end at 200MHz by the end of 1997. Chances are they would've stuck to a plain old Pentium system and saved the extra cash for a rainy day. The same can't and won't be said about those users that bought Pentium Pro systems because they truly needed them, meaning, those that ran the quad processor demons as servers and high end workstations. For them, the processor was worth the cost, and it was what they needed to get the job done.
That last line is key to the success of Intel's Xeon processor, it gets the job done. For a desktop user, and for a gamer, the purpose of having the power of a single or even a dual Pentium III Xeon 500 under the hood of their computer is the same reason car buffs brag about their engines being able to produce more horsepower than most five year olds can count up to. For a website administrator, or anyone looking to run a file/application server, there's definitely a reason and a need to pursue the Xeon as a solution, albeit an expensive one. With the need there, why is it that Xeon motherboards receive so little attention on-line?
Is it because they cost an arm and a leg to buy? Or is it because they don't make Quake 3 run any faster so therefore they "don't really matter?" Regardless of what the reasons are, it is very disappointing to those users that need the information. As AnandTech was in the position, just recently, to purchase a dual processor Xeon board, it's time for AnandTech to take a look at what the Slot-2 Xeon motherboard market has to offer. Long since the release of the Xeon processor, Epox, a company relatively new to the multiprocessor motherboard industry, has finally come out with a relatively cost effective solution for Xeon owners. Modeled after the well designed dual Slot-1 BXB-S, the GXB-M offers everything Epox's first dual processor solution did, with a cost effective twist. However how does that stack up in the Slot-2 motherboard market? Let's find out...
|CPU Interface||Dual Slot-2|
|L2 Cache||N/A (on-chip)|
|Form Factor||Extended ATX|
|Clock Multipliers||4.0x - 5.5x|
|Voltages Supported||2.0v/2.8v (Auto Detect)|
|Memory Slots||4 168pin DIMM Slots|
|Expansion Slots||1 AGP Slot
0 AMR Slot
5 PCI Slots (5 Full Length)
2 ISA Slots (1 Full Length)
|The Extended ATX form factor of the GXB-M is essentially a requirement of the Intel Xeon processor, the space required for a single SC330 (Slot-2) interface is noticeably larger than that of a SC242 (Slot-1) interface, not only that, but you aren't taking into consideration the extra capacitors and resistors that such a design calls for over the good ol' Slot-1 interface of the Pentium II/III and Celeron processors. Because of that, the GXB-M, as well as all other Xeon boards are only available in an Extended ATX form factor. The board is equipped with the same 5/2/1 expansion slot configuration that make the old BXB-S stand out among the more conventional 4/3/1 designs of previous boards.|
|The length of the board does allow for all 5 PCI slots to accept full length PCI cards, however if a PCI card should extend a centimeter (or about half an inch) longer than most other full length cards, 3 of the 5 slots will suddenly become uninhabitable by that particular card. Signs of Epox's eye for design are present in the GXB-M as they were in the BXB-M, such as the positioning of the two IDE connectors such that they do not interfere with the installation of any full length PCI cards. The ability to accept a full length PCI card is very important when considering the amount of full length PCI and AGP cards, for that matter, that are available and widely used in high end workstations/servers. Of the two ISA slots, only the first is capable of accepting a full length card, which isn't too big of an issue considering that the longest of ISA cards are usually out of date controllers or old SB16 cards. Both of which generally have no purpose in a high end workstation/server.|
||The board is outfitted with 4 DIMM
slots, the maximum supported by the 440GX chipset. The memory banks lay parallel to
the 443GX controller chip, that allows for the 2GB memory capacity of the motherboard, a
1GB improvement over the BX chipset. On the opposite side of the 443GX chip are the
dual SC330 interface slots which themselves are separated by two rows of Sanyo
capacitors. The distance between the two connectors is a little over an inch (2.54+
cm), unfortunately that leaves very little room for elaborate cooling devices on the
surfaces of your Xeon processors. The retail Xeon heatsink as well as most 3rd party
low-profile fans should do just fine, however be aware of the space constraints with the
GXB-M (those constraints are present with most Xeon boards). Interestingly enough,
it seems as if Slot-2 boards require the use of a CPU terminator card if only a single
processor is being used in the motherboard. The same used to be a
"requirement" for dual processor Slot-1 motherboards until it was dropped out of
consideration for keeping costs down. Wonder how long this "requirement"
will be around... Needless to say, Epox does supply you with a SC330 CPU terminator
card in the event that you only use a single processor on the board.
Like most high end workstation/server motherboards, the GXB-M features dual ATX power supply connectors for use with a setup of redundant power supplies, a feature that is in demand by those users that value 100% uptime even in the even of a power supply failure. Although power supply failures aren't the most common failures, the longer you run your system, the closer your power supplies get to their rated mean time between failures.