Socket-A Motherboard Preview

VIA VT5276D KM133 Reference Board

Motherboard Specifications
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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.