ABIT KV8-MAX3: Athlon64 and µGuru

Abit KV8-MAX3: BIOS and Overclocking

NO AGP/PCI Lock, Added Multipliers

One of the ongoing issues with the VIA K8T800 chipset has been our criticism that it does not implement PCI/AGP lock. With Abit's history of catering to the Overclocking market, we believed that we would finally see an AGP/PCI fix on a top-line Abit board — if it would ever be seen on a VIA K8T800 chipset. Abit tells us that the PCI/AGP on the VIA do indeed float, and they have implemented additional multipliers to try to extend overclocking on the VIA chipset. Abit even goes so far as to report AGP/PCI frequencies in their SoftMenu readouts.

As you can see, at a FSB setting of 200, Abit reports the PCI/AGP at spec of 33/66.

At our highest stable overclock of 218, Abit shows AGP/PCI now running at 72/36. Our stock ATI card is known to have difficulties above about 72 to 74 on AGP, so this would support our belief that overclocking is being limited by the lack of an AGP/PCI lock.

By 230FSB, Abit reports AGP/PCI at 76/38.

Finally, at a 233FSB setting, the multiplier kicks in and we are back to 66/33 spec on the bus. The problem, of course, is that you have to reach 233 on overclock for the lower multiplier to kick in. We could not reach 233 with our Athlon64.

While we have seen it reported elsewhere on the web that VIA does fix PCI at 33 and allows AGP to float, we can find no evidence supporting that in the Abit BIOS. Frankly, we place more confidence in Abit's Engineers than we do on what is reported at other sites with no evidence. Based on what Abit tells us, we still have every reason to believe there is no AGP/PCI lock on the K8T800 chipset. This is also supported by the fact that we have never been able to overclock as far on a VIA board as we have achieved on an nForce3 chipset motherboard, which does implement AGP/PCI lock.

BIOS

Abit uses the familiar Award BIOS on the KV8-MAX3, and the latest incarnation of the familiar Abit SoftMenu overclocking utility. The available options should be very familiar to the computer enthusiast, who is the target audience for the KV8-MAX3, so we will not repeat the obvious.

Abit has supplied an incredibly complete selection of options in the PC Heath section of the BIOS. There are submenus for Temperature, Voltage, and Fan Speed monitoring, as well as a FanEQ Control section that gives full control of CPU, OTES, and NB fans.

FSB Overclocking Results

Abit prides themselves on their reputation as the “Overclocking” motherboard company. We, therefore, had high hopes that we would see new overclocking highs with our Athlon64.

Front Side Bus Overclocking Testbed
Default Voltage		Maximum Overclock
Processor:	Athlon64 2.0GHz	Athlon64 2.0GHz
CPU Voltage:	1.5V (default)	1.6V
Cooling:	AMD Stock Athlon64 Heatsink/Fan	AMD Stock Athlon64 Heatsink/Fan
Power Supply:	Enermax 465W	Enermax 465W
Maximum OC:	2180MHz (+9%) 218FSB	2180MHz (+9%) 218FSB

The above overclocking setup at default voltage allowed us to reach a stable FSB of 218. As you can see, increasing voltage did not help at all, still topping out at 218. We suspect the issue here is that we have reached the highest AGP speed our 9800 PRO can handle, and that 218 has little to do with our CPU.

Unless Abit finds a way to implement half multipliers or AMD delivers Athlon64 processors that easily reach 233 on overclock or VIA decides they really do need to provide an AGP/PCI lock to compete with other chipsets, then the KV8-MAX3 is handicapped with the only current chipset without the ability to fix AGP/PCI. The VIA chipset, otherwise, is a joy to use and quite fast. However, after every manufacturer has promised an AGP/PCI lock on their VIA board and no one, not even Abit, has been able to deliver one that works, we are skeptical that we will see this major enthusiast issue corrected until VIA redesigns the K8T800 and their other chipsets – none of which have working PCI/AGP locks.