In depth on Intel's MTH
Posted on: 03/24/2000 01:29 PM

As we all know by now, the new i820 and i840 chipsets from Intel are designed to run RDRAM. Since RDRAM is currently $292 for a 64mb stick, it's not too thrilling of an option. Why Intel didn't just go with PC133 SDRam, we'll never know, but... There is hope (sort of). There is a "Memory Translator" that allows the use of SDRam with the new chipsets. Although it seems to suck and causes some problems all it's own, it is there, which gives us some hope. The guys over at PC Accelerate have strapped on their pocket protectors and given us the whole scoop on the MTH.
The Intel 820 and 840 chipsets are based on a completely new and different memory architecture called RDRAM, or Rambus Direct RAM. (see our RDRAM article for details). Both chipsets have native support only for RDRAM memory. The only way for 820 and 840 to support industry standard SDRAM is through use of an additional ASIC chip that converts RDRAM signals to SDRAM signals.

The 820 uses the Memory Translator Hub (MTH) to perform this function, while the 840 employs an SDRAM Memory Repeater Hub (MRH-S) for the job. Both the MTH and the MRH-S are 241-pin BGA chips with exactly the same pinout. The core logic of the two chips is the same. The only difference is the name and the price. The MTH sells to OEMs for less than a third of the MRH-S' $10 price tag. It's typical for Intel to command a much higher price for the part used in server platforms. I'd do the same thing if I were in their shoes.
Mmmmmm... Geeky :-)

Printed from (