Intel's Pentium MMX

Who says you can't teach an old dog new tricks???

     So, early last year when you bought that new computer you opted for Intel's new top of the line "Pentium MMX" to run it, eh?
     At the time you were just sure it would serve your needs for a few years and then you would just buy the newest, fastest chip that Intel had introduced and pop it right in. Fooled us didn't they...

    However, the new SS7 (Super Socket 7) can give you up to a 10% performance boost without overclocking simply by running your processor at the 100 MHz Front Side Bus speed. While the Pentium 166MMX and 200MMX only are clock multiplier locked at 3 and the 233MMX is locked at 3.5 and you can overclock them by running the FSB at 75MHz and 83MHz, you will actually see the best performance by keeping your chip as close to it's actual speed and running it at 100 MHz. This means 200MHz for the 166 & 200 (100MHz x 2) and 250MHz (100MHz x 2.5) for the 233.
    Our first SS7 mainboard (FIC's VA-503+) came before our new processor and like a kid with a new toy, I just couldn't wait to fire it up. The 100MHz FSB really makes the Pentium MMX sing and so I put through it's paces carefully noting scores and times and what I found was that the system runs like a champ in Windows 95 and with a few minor tweaks does equally as well in Win98. The 100MHz FSB (front side bus) pulls a 12% increase in MIPS (millions of instruction per second) and about a 9% increase in MFLOPS (mega floating point operations per second). There was also a reasonable increase in 2D and 3D benchmarks other than Open GL which did increase although negligibly and an amazing 15% increase in cached disk access and read/write scores. Even with my old EDO SIMMs.


     The Pentium MMX is a hummer when it comes to over clocking and the 233 is definitely a pro in this area. Even with an ordinary heat sink and fan it stayed stable at 300MHz (100MHz x 3) although I had to jump the core voltage to a dangerously high 3.3v in order to get it to boot properly. Consequently I do not recommend running it for extended periods at that speed. It purrs like a kitten however with the clock multiplier set at 2.5 and the core voltage at 2.9v and I wouldn't hesitate to leave the machine on for a week at a time.
     The VA-503+ can be set to run at 112MHz although it is undocumented (clk1-1;2, clk2-2;3, clk3-2;3) and although it would boot and run alright for an hour or so, the system eventually failed. However I can't only fault the board or chip for this but rather the increase in the PCI bus speed putting excess strain on the peripherals in conjunction with the other two and the fact that I was using EDO SIMMs as opposed to SDRAM. I have since had several letters from "overclockers" that say their machines run just fine at this speed.

In Conclusion

I can only say that the "Super 7" platform is a great boost to this dying breed of Intel chips and that even if you can't afford a new motherboard and chip combination, if you have a Pentium MMX chip on your existing board. Buy yourself the new motherboard first. Pop in your old chip then sit back and enjoy the performance that kicks in on the 100MHz FSB...

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