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Re: Re: Help! Mathematica on my 500MHz outperforms my GHz machine!
Re. the following: > >Actually, the K7/Athlon uses the external bus/protocol of the DEC >Alpha EV6, which is clocked at 200 MHz. That interface "connects" >with the motherboard chipset. The motherboard chipset then "connects" >independently with the RAM banks. Current K7 boards use the AMD >750/751 chipset which supports 100 MHz (PC100) SDRAM. Upcoming boards >will use the VIA KX133 chipset which has support for PC133 SDRAM. > >The 200 MHz EV6 processor bus allows plenty of "back-end" bandwidth >and low latency for multiprocessing and such. > >Vijay Ram ....I read a recent article in PC Magazine about overclocking in Pentium systems which stated that overclocking was accomplished by re-setting a multiplier (in BIOS, or via MOBO jumpers) that determines CPU clock from the system bus speed, i.e. to get a 500MHz CPU clock on a system with a 100MHz system bus, set the multiplier to 5. Now, if this is basically how Athlon CPU clock speeds are set, which bus speed is used as the basis for multiplication, the DEC EV6 200MHz bus, or the RAM & system bus (100 or 133 MHz)? If not, then just how are Athlon chips clocked and overclocked? Suppose Athlon MOBOs determine CPU clock speed by multiplying the slower system bus speed. If one misunderstood this, and assumed that one could get a 1GHZ Athlon by setting the multiplier to 5.0, one would only have a 500MHz CPU! Could this be what happened to Jaczek? By the way, as a hardware ignoramus, I found the PC Mag article very interesting. Overclocking, according to it, is not something you should try at home, unless you can afford to write off an Athlon or two to the learning experience. Sometimes overclocking requires higher CPU voltages, always it generates more heat in the CPU. If it isn't done just right, you can shorten CPU life significantly. -mark harderm at ucs.orst.edu