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AMD's Super Bypass - AMD Improves their 750 Chipset

Reflecting Back On The Athlon's Bus

I wanted to quickly touch on the Athlon's CPU and memory bus. There is a lot of confusion out there regarding the memory that Athlon platforms use. A lot of people are confusing the front side bus (FSB) with the memory bus. The Athlon's FSB is able to communicate with the north bridge at 200 MHz while the memory interface only runs at 100 MHz. The FSB is running at a double data rate (100 MHz X 2). That's how the CPU is able to run with a FSB of 200 MHz. The memory only runs at 100 MHz! So if you are looking to purchase memory for your Athlon system all you need is PC100 SDRAM. If you would like to investigate more information on the Athlon processor and chipset please check out The New Athlon Processor - AMD Is Finally Overtaking Intel article.

The Good, The Bad, And The Ugly

Well I've covered the good, which is that the super bypass feature will provide better performance. What could possibly be bad? The bad is that you cannot physically identify if a board is equipped with a super bypass supported AMD 751 chip. That's right! There are no markings on the chip that reflect if it has super bypass or not. The only way to identify if a chipset has super bypass is through the PCI registers. The BIOS can check this special register to see if super bypass is available or not. The Gigabyte 7IX platform that I received had a setting in the Award BIOS under the "Advanced Chipset Features" section called "Bypass enable". I seriously doubt that production motherboard BIOS will have this option, most likely this feature will be transparent (automatically set) to the user. If you do try to enable super bypass on a non-supported motherboard you will see no benefit since the feature is broken or non-existent. I guess this is why AMD has been so quiet about promoting this new feature.