DDR333 For Athlon: VIA KT333 vs. KT266A

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Ultra-DMA/133: Currently Supports Maxtor Only

The new Southbridge VT8233A (recognizable by the added "A") has an integrated Ultra-DMA/133 IDE controller, among other features. This means that technically, a data transfer rate of 133 MB/s is possible, but an overhead of about 10% data should be deducted. Current hard drives with 7200 rpm just barely achieve a data rate of 50 MB/s, so with ATA/133, you've got enough reserves to keep you up-to-date for the next two years. However, there is one restriction: modern hard drives are equipped with 8 MB cache, so the physical limit of 133 MB/s is quickly reached. It can be determined that Ultra-DMA/133 hard drives only make sense starting from a specific minimum size of the internal cache (from approx. 4 MB), as well as high read and write speeds for the ATA/133 interface. For the traditional CD ROM, DVD or CD RW drives, an Ultra-DMA/133 interface is superfluous. In the end, even the fastest 16x DVD drives can achieve a maximum of 15 MB/s. An important note: compared to Ultra-DMA/100, all connections, including the cable connection, are the same .