FBDIMM Support On Intel PowerMac/XServe?

How FB-DIMM Memories Work

Great link!!! Thanks for the info.

Using serial communication the number of wires needed to connect the chipset to the memory module is lower and also allows the creating of more memory channels, what [sic] increases memory performance.

My intuition was completely backwards. I would have thought that parallel memory controller communication would be faster. No wonder I'm in the software field, not the hardware field!

My intuition was completely backwards. I would have thought that parallel memory controller communication would be faster. No wonder I'm in the software field, not the hardware field!

Hehe, remember that serial ATA is a faster interface than parallel ATA :)

....and memory capacities up to 64 GB are supported....

Just in time for Windows Vista!

My intuition was completely backwards. I would have thought that parallel memory controller communication would be faster. No wonder I'm in the software field, not the hardware field!

Your intuition is correct. FBDIMMs are not faster. The current bus based memory interfaces can only support 2 to 4 DIMMs at high speeds. FBDIMMs simply enable the same amount of data to be carried over smaller number of wires and thus make it possible to attach more memory (i.e. more DIMMs) to the system.

Using FBDIMMs, the number of pins required on the memory controller per memory channel is less, thus it is also possible to build memory controller that support more channels (4, 6 or 8) in a reasonable sized package.

So FBDIMMs enable larger memory configurations or more bandwidth. But they actually increase the memory latency since the data has to be serialized on the DIMM and deserialized when it reaches the memory controller.

FBDIMMs are a good fit for server configurations which require a lot of memory or a lot of bandwidth, but not a good fit for applications that require low memory access latency.

so good for servers... not so good for desktops?

so good for servers... not so good for desktops?

Most of the time your desktop's bottleneck will probally not be the RAM.

Intel was previously rumored to be contracted with designing the next-generation PowerMac/Mac Pro's motherboard design.

No way! There's going to be intel chips/ mobo in the rest of apple's lineup?! :rolleyes:

Most of the time your desktop's bottleneck will probally not be the RAM.

so will these end up in some of apple's desktops then?