High Performance Thanks To 83 MHz System Clock

Previous Next
1:03 PM - 07/25/2000 by Frank Völkel

When the Pentium and Pentium MMX were popular, the maximum system clock was 66 MHz. For those CPUs the L2 cache resides on a Socket7 board and not on the die of the processor. As a consequence, the L2 cache and the system memory are accessed at system clock frequency. In order to run a modern K6-2+ at 500 MHz, it is necessary to set the system clock above the official specification. On most boards the jumper settings are noted for all clock rates up to 75 MHz. The highest possible clock rates of the P55T2P4 series are 83 MHz and with this frequency the highest performance is achieved. We must clearly point out here that in this case the PCI bus as well as the ISA interface are significantly overclocked. Because of the higher PCI clock of 41.5 MHz (instead of the default 33 MHz) some older graphics cards might run into problems. A Riva 128 graphics card in combination with two Voodoo2 cards (SLI mode) are an ideal solution. The undocumented settings for a system clock of 83 MHz are listed in the bottom table. The system clock value of 108 MHz, which is also listed, has no meaning in practice because the system refuses to boot at this frequency.

The jumpers JP8, JP9 and JP10 set the system clock. To operate the AMD K6-2+/500 successfully, the system clock should be set to 83 MHz.
FSB JP8 JP9 JP10 Note
50 MHz 2-3 2-3 2-3
55 MHz 1-2 2-3 2-3
60 MHz 2-3 2-3 1-2
66 MHz 2-3 1-2 2-3
68 MHz 1-2 1-2 1-2 turbo mode
75 MHz 1-2 2-3 1-2 runs very stable
83 MHz 1-2 1-2 2-3 runs stable
108 MHz 2-3 1-2 1-2 not working
The table shows all clock rates for the system clock. The 108 MHz value has no practical meaning, however.
Talkback
Comments are closed on this page.

Sponsored links

All about Tweaking & Tuning
 Latest Tweaking & Tuning articles
All Tweaking & Tuning articles

Newsletters


  • Ask your question about IT issues
  • Post

Partners

The Games selection

adventure : Ray Adventure game, South Park style. Pick the way the story goes by picking an answer among those offered.
crazy : Xiao Xiao 7 A great fight scene from the animation movies Xiao Xiao.
Ads

Sponsored links