Introduction

For the Thunderbird introduction, we asked manufacturers to send us their KT133 Socket-A boards so we could get an idea of what type of motherboard support the Thunderbird and Duron would be receiving at launch time. Three manufacturers, FIC, Gigabyte, and MSI had samples available and arrived in the AnandTech lab by June 5, the day of the Thunderbird launch. VIA also provided a KM133 reference board and AMD's evaluation system included a Compaq OEM motherboard.

This preview is designed to show a bit about what we can expect on the Socket-A platform. All of these boards are pre-production and specifications are bound to change. We decided against performance and stability tests on such early boards, but rest assured we'll have individual reviews and a roundup of Socket-A boards as soon as final evaluation samples are available.

Unlike the original Athlon release, motherboard support for AMD's Socket-A CPU's should not be a problem at all. Just about every motherboard manufacturer has announced a Socket-A solution this week at Computex 2000 in conjunction with the Thunderbird launch. The summary at the end of this article also includes a bit about some of those notable boards announced this week, including a board from QDI that claims to disable the Thunderbird / Duron multiplier lock. We'll have complete Computex 2000 coverage next week, with even more Socket-A motherboard previews among quite a few other things.

Compaq Pipeline-1

Motherboard Specifications
Click to Enlarge
CPU Interface	Socket-A
Chipset	VIA KT133 VIA 8363 North Bridge VIA 686A South Bridge
L2 Cache	N/A (on-chip)
Form Factor	ATX
Bus Speeds	100
Voltages Supported	Auto Detect
Memory Slots	3 168-pin DIMM Slots
Expansion Slots	0 AMR Slots 1 AGP Slot 5 PCI Slots 0 ISA Slots
AC'97	None
BIOS	Compaq OEM

The Compaq Pipeline-1 was the board included in our evaluation system from AMD. It turns out the Pipeline-1 is just an OEM version of the FIC AZ-11 with a Compaq specific BIOS, without any tweaking options.

FIC AZ-11

Motherboard Specifications
Click to Enlarge
CPU Interface	Socket-A
Chipset	VIA KT133 VIA 8363 North Bridge VIA 686A South Bridge
L2 Cache	N/A (on-chip)
Form Factor	ATX
Bus Speeds	100 / 102 / 104 / 106 / 107 / 108 109 / 110 / 111 / 112 / 133
Voltages Supported	Auto Detect
Memory Slots	3 168-pin DIMM Slots
Expansion Slots	0 AMR Slots 1 AGP Slot 5 PCI Slots 0 ISA Slots
AC'97	Sigmatel STAC9744T
BIOS	Award 6.00PG

The first revision of the FIC SD-11 was one of the worst boards to come through the AnandTech lab. Some dilligent work on the board allowed later revs of the SD-11 to become a much more respectable Athlon motherboard solution. A number of large OEM's certainly believed in the SD-11 and used the board in their systems. That board was a very unique one, with a sprawling PCB layout, optional onboard IEEE-1394 Firewire, and the first to use a hybrid AMD 750 North Bridge / VIA 686A South Bridge chipset.

FIC's first Socket-A board, the AZ-11 is a much more conventional design with the majority of the kinks worked out already. Serving as a testament to this fact, the AZ-11 is the Compaq reference board that AMD shipped with their evaluation Thunderbird systems. The only big difference is in the BIOS, where the FIC version uses a traditional Award BIOS and the Compaq uses a custom OEM Compaq BIOS. As such, the FIC is obviously the more tweakable version.

Our pre-production AZ-11 featured FSB speeds of 100 / 102 / 104 / 106 / 107 / 108 / 109 / 110 / 111 / 112 / 133, although our early overclocking experiments with the KT133 chipset have only been able to hit FSB speeds of 105 MHz. On the more mature Slot-A platforms, we were able to get in the vicinity of 110 MHz. The available FSB speeds and the stability of those settings could easily change for the final board. No core voltage tweaks were available in the revision of the BIOS that we tested.

The AZ-11 is still a relatively large board, although not as big as its older brother SD-11. Interestingly, quite a bit of space on the left side of the board remains unused. FIC could have easily fit in another PCI slot or a PCI/ISA shared slot. Also interesting is the fact that there is no AMR slot on the board. Many of you will rejoice at this fact, but it is nevertheless odd for a Compaq to choose a board without such support.

At first glance, the AZ-11 appears to be missing the second serial port connector. Rather, the PCB was designed such that either the KT133 or KM133 chipset, which are pin compatible, could be used. The KM133 is identical to the KT133, but has integrated Savage4 video. That "missing" serial port is where the monitor port would be if the KM133 were included.

Gigabyte GA-7ZM

Motherboard Specifications
Click to Enlarge
CPU Interface	Socket-A
Chipset	VIA KT133 VIA 8363 North Bridge VIA 686A South Bridge
L2 Cache	N/A (on-chip)
Form Factor	ATX
Bus Speeds	100 / 102 / 104 / 106 / 107 / 108 109 / 110 / 111 / 112 / 133
Voltages Supported	Auto Detect
Memory Slots	3 168-pin DIMM Slots
Expansion Slots	1 AGP Slot 3 PCI Slots 1 AMR Slot (shared) 0 ISA Slots
AC'97	Analog Devices AD1881A
BIOS	AMI Simple BIOS 1.22

Gigabyte's GA-7ZM certainly seems to be the board closest to being ready for production. Our evaluation sample was labeled revision 2.2 and didn't have any hand soldered components as we found on the rest of the boards. The GA-7ZM is a microATX board, although Gigabyte will have a full fledged ATX board on the market soon as well, most likely with additional features like DualBIOS.

Like other recent Gigabyte boards, the GA-7ZM uses the AMI Simple BIOS with a fully jumpered CPU setup. FSB speeds include 95 / 100 / 105 / 110 / 113 / 115 / 117 / 133, although our early overclocking experiments with the KT133 chipset have only been able to hit FSB speeds of 105 MHz. On the more mature Slot-A platforms, we were able to get in the vicinity of 110 MHz. The available FSB speeds and the stability of those settings could easily change with the final board. Core voltage adjustment was not available on this revision of the board.

MSI K7T Pro

Motherboard Specifications
Click to Enlarge
CPU Interface	Socket-A
Chipset	VIA KT133 VIA 8363 North Bridge VIA 686A South Bridge
L2 Cache	N/A (on-chip)
Form Factor	ATX
Bus Speeds	100 / 101 / 103 / 105 / 107 / 109 / 110 / 111 113 / 115 / 117 / 120 / 125 / 130 / 133 / 135 137 / 139 / 140 / 143 / 145 / 148 / 150 / 155 / 167
Voltages Supported	Auto Detect Adjustable from 1.6V - 1.8V
Memory Slots	3 168-pin DIMM Slots
Expansion Slots	1 AGP Slot 6 PCI Slots 0 ISA Slots 1 CNR Slot (shared)
AC'97	Analog Devices AD1881
BIOS	Award 6.00PG

The MSI K7T Pro was by far most feature packed of the early boards we received. It had by far the most FSB speeds, including 100 / 101 / 103 / 105 / 107 / 109 / 110 / 111/ 113 / 115 / 117 / 120 / 125 / 130 / 133 / 135 / 137 / 139 / 140 / 143 / 145 / 148 / 150 / 155 / 167. However, we must point out once again that our early overclocking experiments with the KT133 chipset have only been able to hit FSB speeds of 105 MHz. On the more mature Slot-A platforms, we were able to get in the vicinity of 110 MHz. The available FSB speeds and the stability of those settings could easily change for the final board.

Core voltage adjustment from 1.6-1.8V was also available for pushing that overclocked CPU to its maximum speed. Four monster 4700 uF and three equally sized 3900uF capacitors make sure that the CPU gets enough power.

A total of 3 DIMM slots, 6 PCI slots, and a shared CNR slot cover the expansion possibilities. Like the K7 Pro, the K7T Pro features a PCI arbiter chip that allows all 6 of those PCI slots to host bus mastering cards. The inclusion of the CNR slot is a bit unique since the VIA 686A Super South Bridge was designed with AMR in mind only. We'll have to wait and see how MSI plans to handle CNR cards. We are happy to see the CNR slot become a shared one, rather than take up precious PCB space that could be allocated to a PCI slot. We expect to see this trend become more and more common on future motherboards.

VIA VT5276D KM133 Reference Board

Motherboard Specifications
Click to Enlarge
CPU Interface	Socket-A
Chipset	VIA KM133 VIA 8365 North Bridge VIA 686A South Bridge
L2 Cache	N/A (on-chip)
Form Factor	ATX
Bus Speeds	66 / 75 / 79 / 83 / 100 / 110 / 115 120 / 124 / 129 / 133 / 138 / 143
Voltages Supported	Auto Detect
Memory Slots	3 168-pin DIMM Slots
Expansion Slots	1 AGP Slot 2 PCI Slots 0 ISA Slots 1 AMR Slot
AC'97	Sigmatel STAC9744T
BIOS	Award 6.00PG

While the VIA reference board will never be available forsale directly from VIA, it does give us an idea of what VIA gave manufacturers to work with as a starting point. Interestingly, none of the boards we've looked at so far follows this reference design, but then again, FIC, Gigabyte, and MSI have never simply copied the reference design.

The VT5276D is the only KM133 board we received in our initial group of Socket-A boards. You'll notice that despite the integrated Savage4 graphics, there is still an AGP 4X slot on the board. Plugging in an AGP graphics card automatically disables the onboard video and the board acts just like a standard KT133.

Award BIOS 6.00PG is used on the reference board, but despite Award's built in support for jumperless CPU setup, the VT5276D still uses a completely jumpered setup. What is interesting here is that this reference board actually has mutliplier control via jumpers. Unfortunately, the multiplier lock of the Socket-A Thunderbird and Duron is definitely implemented on the chip itself as the multiplier jumpers had no effect in our testing. Recent discussions of breaking the Thunderbird / Duron multiplier lock certainly give hope to all the overclockers out there, but nothing conclusive has been discovered yet.

The strange selection of FSB speeds is due simply to the fact that this board was never meant for production, so we won't likely be seeing any boards with speeds like 66 / 75 / 79 / 83 like this one. Typical of a reference BIOS are a number of settings that directly affect the chipset registers, but are not labeled as anything comprehensible.

Other Announced Boards

A plethora of boards were announced simultaneously with the launch of the Thunderbird at Computex 2000 on June 5. While those boards were not available for this preview, we'd like to briefly mention a few notable products that are on the way.

ASUS has their A7V, the successor to the popular K7V, our favorite Athlon motherboard. Unique features of the A7V include an AGP Pro slot and an optional Promise Ultra ATA 100 controller.

MSI's second Socket-A board, the K7T Master, is already being readied. The K7T Master adds AGP Pro and on-board SCSI, a first for an Athlon motherboard.

QDI has announced a Socket-A motherboard, the KinetiZ 7T, that allows breaking of the Thunderbird / Duron multiplier lock by using pins labeled as "reserved" in AMD's documentation. Not much else is known about this board at the moment, but if this ability is truly available, the KinetiZ 7T will be a huge success among overclockers.

Summary

Those are the 5 boards that arrived in the AnandTech lab in time for the Thunderbird review. We'll have many more Socket-A motherboard previews, and much much more, in our Computex 2000 coverage next week. Of course, we'll have complete Socket-A motherboard reviews and a roundup as soon as production boards are available.