Super7 Upgrade Guide: The K6-2+ and K6-3+ Processors

The K6-2+ and K6-3+ in Desktops

The decision to withhold the K6-2+ and K6-3+ processors from the retail market frustrated many Super7 desktop owners. It was thought that the refusal to sell K6-2+ and K6-3+ processors for use in desktops marked the death of the Super7 platform. Hopes were not discouraged for long, however. Realizing that the K6-2+ and the K6-3+ processors were only different from the original K6 series processors in the voltage that runs the core and the recognition of the BIOS, a few people entertained the idea of using the Socket7 version of the + series chips in desktop systems. It was not long before help from motherboard manufacturers helped them to succeed.

By revealing "hidden" voltage settings and providing BIOS updates that allowed a motherboard to recognize the new processors, it was not long before home users were experimenting with desktop K6-2+ and K6-3+ systems. The chips, which are rather easily available on the retail market in OEM form, can be found at prices very close to the original K6-2 and K6-3 prices, making the appeal of the + series chips even greater. Plus, with the possibility of greater overclockability due to the + series' 0.18 micron process, Super7 system owners rejoiced when some users reported successful adaptation of the K6-2+ and K6-3+ chips to the desktop arena.

The problem is that not all motherboards have voltage jumpers capable of limiting the Vcore voltage to the 1.4 - 2.0 volts that the K6-2+ and K6-3+ required. As mentioned before, previous K6-2 and K6-3 chips ran off a 2.2 - 2.8 Vcore socket, meaning just replacing and old K6-2 or K6-3 with one of the + models would result in frying the chip. Some users were in luck when the manufacturer of their motherboard released settings that altered the Vcore of the motherboard down to the proper level for the + series processors. Others, however, did not have as much luck and were left looking for the proper voltage settings on their own.

As mentioned before, the second roadblock encountered when using the + processors in desktop systems comes with the BIOS. Since the system BIOS must correctly recognize the processor in order to make it work, a motherboard's BIOS would have to be updated to correctly relay the processor information to the system. This time users were completely at the mercy of motherboard manufacturers who were the only ones that could provide the correct BIOS flash.

Luckily, many motherboards with the ability to provide the correct voltage to the + series CPUs also had BIOS flashes. Which Super7 motherboards work properly with the K6-2+ and K6-3+ processors? To answer that question, we dove deep into storage and tried a K6-3+ in the Super7 boards we still had. Below is a table summarizing the results.

Keep in mind this is by and far not a complete list. In addition, we did not go to extreme measures to obtain the proper voltage settings, meaning that we did not modify the motherboard in any form in order to obtain the correct voltage. There are likely ways to modify some boards in order to allow only 1.4 - 2.0 volts through and are surely some tweak guides out there, but we stuck to using the original board equipment only.

As is apparent by the results of our testing, only a handful of motherboards offer full K6+ series support. Surprisingly, we were only able to eliminate three motherboards based on voltage support. Only the FIC PA-2007, the ABIT IT5H, and the Supermicro P5MMA did not offer voltage settings for the 2.0 volt 450 MHz K6-3+ that we used for compatibility testing. All other boards offered the required 2.0 volt setting, meaning that the rest was up to the BIOS.

It was in the BIOS that we encountered the most compatibility problems. Every board tested was flashed with the most recent BIOS version, yet few boards worked. Some would successfully flash, only to not properly detect the CPU while others would not even make it past a memory count. Out of the eleven boards tested, only three provided the correct combination of voltage settings and BIOS support necessary to power a K6-2+ or a K6-3+ processor.

So, now that we can use the K6-2+ and K6-3+ processors in some Super7 systems, let's see how the perform compared to their original incarnations. Once again, keep in mind that only eleven of the hundreds of Super7 motherboards out there were tested and no "hidden" features were enabled to allow support. As always, your results may vary.