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Mattman · 06-03-2000, 07:40 PM

I found this quote in "Showdown at 133mhz, Part 2", A Tom's Hardware article:

As overclocking became more and more popular and after PC133 SDRAM for a memory clock of 133 MHz became available, people started running 440BX beyond spec at 133 MHz FSB. This procedure has the following issues.

--The front side bus of the CPU is running 133 MHz instead of 100 MHz, which is no problem even for processors marked for 100 MHz FSB, but certainly not for the latest Coppermine-CPUs that are supposed to run at this clock.
--The 'North Bridge' of BX is also running at 133 MHz instead of 100 MHz and thus out of spec. However, this does hardly do any harm to the chipset, it doesn't even get significantly hotter.
--The PCI-bus can still run at 33 MHz clock, because BX is able to divide the FSB-clock by 4 and 133 / 4 = 33.
--The 'South Bridge' of BX is not touched by this procedure, because it is connected to the north bridge via the PCI-bus. As long as the PCI-bus runs in spec, the south bridge does that too, so that I/O-ports, the integrated IDE controller and all the other components hosted by the south bridge continue to work normally.
--The only real problem with a BX overclocked to 133 MHz FSB is the AGP. AGP is supposed to run at 66 MHz and BX is able to ensure that by dividing the 100 MHz FSB by 1.5. Unfortunately Intel decided against the inclusion of a divider of 2 as well, which is why the AGP is doomed to running at 133 / 1.5 = 88.8 MHz. Running the AGP 33% beyond spec can produce a fair amount of trouble with AGP-graphics cards. Some have no problem, but many will simply freeze the whole system as soon as you switch to a 3D-application that is using the AGP. Fortunately our reference graphics card with NVIDIA's GeForce256-chip is not troubled by 89 MHz AGP-clock at all, so that the testing with a BX-board at 133 MHZ FSB was a piece of cake. The system remained absolutely stable, and you can believe me that I mean what I say, different to so many other overclocking-horney people, who think that a system that needs rebooting only three times/day is already 'rock stable'.

Getting a decent video card and PC133 RAM should be enough to allow you to reach 133mhz. I'd bet money that Tom isn't lying when he says the Geforce will run at 89mhz no problem. The whole article can be found at http://www.tomshardware.com/mainboar...308/index.html .

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Life without computers would be like the world without war.

06-03-2000, 07:40 PM	#18
Mattman Member (9 bit) Join Date: Nov 1999 Posts: 507	I found this quote in "Showdown at 133mhz, Part 2", A Tom's Hardware article: As overclocking became more and more popular and after PC133 SDRAM for a memory clock of 133 MHz became available, people started running 440BX beyond spec at 133 MHz FSB. This procedure has the following issues. --The front side bus of the CPU is running 133 MHz instead of 100 MHz, which is no problem even for processors marked for 100 MHz FSB, but certainly not for the latest Coppermine-CPUs that are supposed to run at this clock. --The 'North Bridge' of BX is also running at 133 MHz instead of 100 MHz and thus out of spec. However, this does hardly do any harm to the chipset, it doesn't even get significantly hotter. --The PCI-bus can still run at 33 MHz clock, because BX is able to divide the FSB-clock by 4 and 133 / 4 = 33. --The 'South Bridge' of BX is not touched by this procedure, because it is connected to the north bridge via the PCI-bus. As long as the PCI-bus runs in spec, the south bridge does that too, so that I/O-ports, the integrated IDE controller and all the other components hosted by the south bridge continue to work normally. --The only real problem with a BX overclocked to 133 MHz FSB is the AGP. AGP is supposed to run at 66 MHz and BX is able to ensure that by dividing the 100 MHz FSB by 1.5. Unfortunately Intel decided against the inclusion of a divider of 2 as well, which is why the AGP is doomed to running at 133 / 1.5 = 88.8 MHz. Running the AGP 33% beyond spec can produce a fair amount of trouble with AGP-graphics cards. Some have no problem, but many will simply freeze the whole system as soon as you switch to a 3D-application that is using the AGP. Fortunately our reference graphics card with NVIDIA's GeForce256-chip is not troubled by 89 MHz AGP-clock at all, so that the testing with a BX-board at 133 MHZ FSB was a piece of cake. The system remained absolutely stable, and you can believe me that I mean what I say, different to so many other overclocking-horney people, who think that a system that needs rebooting only three times/day is already 'rock stable'. Getting a decent video card and PC133 RAM should be enough to allow you to reach 133mhz. I'd bet money that Tom isn't lying when he says the Geforce will run at 89mhz no problem. The whole article can be found at http://www.tomshardware.com/mainboar...308/index.html . ------------------ Life without computers would be like the world without war.