hardware fixes (AMD K6, K6-2 and K6-III in Socket 7 boards)


Most older mainboards feature only Socket 7 instead of the required SuperSocket 7. AMD K6-2 and K6-III are designed for a front side bus (FSB) of 100 MHz provided by SuperSocket 7. Socket 7 only allows speeds of up to 66MHz FSB although some manufacturers specified their boards for 75/83 MHz. So the only way of getting your K6 running at full speed is lowering the FSB to 66/75/83MHz and rising the multiplicator (4.5 x 66MHz is same as 3.0 x 100MHz). Using the fast K6 processors in such older boards means something like underclocking. But for your computer it is more than a small performance boost.
The following table shows the official settings for AMD K6 CPUs and on the right side usable settings in your board. Green fits perfectly, yellow uses a lower speed than possible and red is definitly overclocking. All values are the closest possible with the given FSB.

Note: To get the multiplier value of 6.0x you need a K6-2CXT or K6-III which take the jumpered 2.0x as 6.0x.

AMD K6 / K6-2 / K6-III
CPU Vcore official settings Socket7 w/ FSB66 Socket7 w/ FSB75 Socket 7 w/ FSB83
K6 166MHz 2.9V 166= 66 x 2.5      
K6 200MHz 2.9V 200= 66 x 3.0      
K6 233MHz 2.2V / 3.2V 233= 66 x 3.5      
K6 266MHz 2.2V 266= 66 x 4.0      
K6 300MHz 2.2V 300= 66 x 4.5      
           
K6-2 233MHz 2.2V 233= 66 x 3.5      
K6-2 266MHz 2.2V 266= 66 x 4.0      
K6-2 300MHz 2.2V 300= 66 x 4.5      
K6-2 333MHz 2.2V 333= 66 x 5.0      
K6-2 366MHz 2.2V 366= 66 x 5.5      
K6-2CXT 300MHz 2.2V 300= 100 x 3.0 300= 66 x 4.5 300= 75 x 4.0 290= 83 x 3.5
K6-2CXT 333MHz 2.2V 333= 95 x 3.5 333= 66 x 5.0 338= 75 x 4.5 333= 83 x 4.0
K6-2CXT 350MHz 2.2V 350= 100 x 3.5 366= 66 x 5.5 338= 75 x 4.5 333= 83 x 4.0
K6-2CXT 380MHz 2.2V 380= 95 x 4.0 366= 66 x 5.5 375= 75 x 5.0 374= 83 x 4.5
K6-2CXT 400MHz 2.2V 400= 100 x 4.0 400= 66 x 6.0 413= 75 x 5.5 415= 83 x 5.0
K6-2CXT 450MHz 2.2V / 2.4V 450= 100 x4.5   450= 75 x 6.0 457= 83 x 5.5
K6-2CXT 475MHz 2.2V / 2.4V 475= 95 x 5.0     457= 83 x 5.5
K6-2CXT 500MHz 2.2V 500= 100 x 5.0     500= 83 x 6.0
K6-2CXT 533MHz 2.2V 533= 97 x 5.5      
           
K6-III 380MHz 2.4V 380= 95 x 4.0 366= 66 x 5.5 375= 75 x 5.0 374= 83 x 4.5
K6-III 400MHz 2.2V / 2.4V 400= 100 x 4.0 400= 66 x 6.0 413= 75 x 5.5 415= 83 x 5.0
K6-III 450MHz 2.2V / 2.4V 450= 100 x 4.5   450= 75 x 6.0 457= 83 x 5.5
K6-III 500MHz 2.2 V 500= 100 x 5.0     500= 83 x 6.0

For correct settings of your multiplicator jumpers refer to this page.

AMD K6 has higher power consumption than intel Pentium. Therefore you'll have to check if your board supports every clock rate. Otherwise you'll make a nice barbecue out of your voltage regulators.
This table lists supported current draw for many older boards.
This table lists power consumption of AMD K6 and other CPUs.
Power Consumption (W [Watt]) = Core Voltage (V [Volt]) * Current draw (A [Ampere])

Supported boards:
ASUS
Abit
AOpen
Chaintech
Elitegroup
FIC (First International Computer)
Gigabyte
Iwill
NMC
PC-Chips
Tyan