All Aboard! P4 with 200 MHz FSB and the i875P Dual DDR400 Chipset

Overview Of Memory Bandwidths

In asynchronous mode, because of the factor of 5/4 when using a 200 MHz FSB CPU, the result is a 160 MHz memory clock (DDR320). If you install a 133 MHz FSB CPU onto the board, then numerator and denominator switch to 4/5 - and the result here is 166 MHz (DDR333).

Swipe to scroll horizontally
FSBMemoryFSB/Memory
100 - 132 MHzDDR266 (133 MHz)3/4
133 - 199 MHzDDR266 (133 MHz)DDR333 (166 MHz)1/14/5
200 - (overclock) MHzDDR266 (133 MHz)DDR320 (160 MHz)DDR400 (200 MHz)3/25/41/1
Swipe to scroll horizontally
Memory TypeLabelingEff. ClockData BusBandwidth
SDRAM66PC6666 MHz64 Bit0.5 GB/s
SDRAM100PC100100 MHz64 Bit0.8 GB/s
SDRAM133PC133133 MHz64 Bit1.1 GB/s
DDR266PC2100133 MHz64 Bit2.1 GB/s
DDR266-DualPC2100133 MHz64 Bit4.2 GB/s
DDR333PC2700166 MHz64 Bit2.7 GB/s
DDR333-DualPC2700166 MHz64 Bit5.4 GB/s
DDR400PC3200200 MHz64 Bit3.2 GB/s
DDR400-DualPC3200200 MHz64 Bit6.4 GB/s
RDRAM 400PC800400 MHz16 Bit1.6 GB/s
RDRAM 400-DualPC800400 MHz2 x 16 Bit3.2 GB/s
RDRAM 533-DualPC1066533 MHz2 x 16 Bit4.2 GB/s
RDRAM 600-DualPC1200600 MHz2 x 16 Bit4.8 GB/s
Uwe Scheffel