Pentium 4 with Dual DDR: Endurance Test of Seven Motherboards with the Granite Bay Chipset

Clocking Games, Synchronous Transfer And 1530 MHz Arms Races

Following an unprecedented race by manufacturers to see who arms their products with the highest clock rates, the fastest available DDR memory chip can now work with well above 200 MHz (DDR433 from Corsair). There are actually no corresponding chipsets for this, and none are expected.

DDR433 - no such thing, but that’s how fast it is. The manufacturer guarantees 216 MHz.

So numbers games like this still leave room for freaks and overclockers. Until now, not even DDR400 has caught on as a mainstream thing ; the performance edge over DDR333 - if there even is one - is too minimal.

The reason for the non-existent power increase is the fact that the memory can no longer be run synchronously with the processor speed or, more precisely, the FSB speed. An Athlon XP FSB with a speed of 266/ 133 MHz (double-pumped), for example, works excellently and without delays with a memory run at the same speed ; so does the Pentium 4 at 533/ 133 MHz (quad-pumped), including DDR266 at 133 MHz (or PC1066 RDRAM at 533 MHz double-pumped).

However, if the main memory is operated asynchronously, wait times need to be figured in now and then. The data transfer is like jumping onto a moving merry-go-round : more often than not, you have to wait for your "chance." With synchronous or pseudo-synchronous transfer, there are no unnecessary wait times, which is why Intel prefers this model in the E7205.

The next generation of Pentium 4 with 800 MHz FSB (200 MHz quad-pumped), too, is only being operated synchronously for now, and it will actually work with DDR400.