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An Overview of Quad Band Memory
tedgyz writes "AnandTech has a short article on a new memory technology from Via, called Quad Band Memory (QBM). Rather than using dual-channel DDR to increase bandwidth, they use phase-shifting inside the memory modules to accomplish the same goal. The end result is simpler (and presumably cheaper) motherboard designs that are backwards compatible with current DDR modules. The downside? It is currently only going to available in a P4 chipset that Intel has not authorized."
Via made this, via makes chipsets. Seems likely they'll make chipsets that support this.
Let's see, one PLL... damn, I don't know if I can afford the extra six cents!
Well, actually, it won't be that cheap. When I was in college working on my senior thesis (Fall 2001), we had an application where we needed to use a PLL in a 2.4GHz transmitter circuit. The thing was approximately 1cm x 2cm x 0.5cm, and cost around $25, and it was damn hard to find. Now, that piece would obviously be far too large and noisy for use on a memory chip (but maybe not)... but the point remains, a PLL that needs to operate in the 100's of megahertz to gigahertz range AND be electrically quiet enough would, I'm sure, jack up the price more than marginally. Now, that $25 piece is all well and good for some flakey-ass collegetransmitter, but this chip is gonna need something that's low-noise, high-gain, and a bunch of other characteristics that WILL make it much more expensive.
Of course, you also gotta take into account that the PLL will (most likely) be hybridized (i.e. wafer removed and built custom onto the chip) and mass-produced, both of which will tend to drive the price down
On the flip side, though, we've become used to buying $20 sticks of RAM, so it might seem pricey at first
"If at first you don't succeed, lower your standards."
Because of the pin-compatible DDR interface, QBM chipsets will be able to use both regular DDR SDRAM modules as well as QBM modules.
That's a GREAT feature. If i have 1GB of DDR ram and only enough money to upgrade the mobo, i'd go with QBM because of this. Then later on the switch could be more gradual. Backwards compatability is a good thing, just look at the PS2 and how well it sells.
DDR333=2.7GB/sec bandwidth
QBM667=5.3GB/sec bandwidth
Double the bandwidth with small modifications to a regular DDR chip has potential for growth.
It seems that the only problem now is that it won't be out until the end of Q1 2003, and it will be on P4s... hopefully they won't have Pallidium too.
-=Errors always defy logic.=-
This is a link to kentron's FAQ about Quad Band Memory.
http://www.theddrzone.com/news.asp?id=731
Via has not explicitly licensed the P4 bus. Via insists it has rights to the necessary patents through the purchase of Cyrix. If Intel officially approves this arrangement then they may lose some licensing sales in the future by setting a precedent.
The whole thing is kind of silly unless Intel is making money hand over foot in the chipset market. I wonder if their motivation to discourage 3rd party chipset development is to lock down control over various platform technologies? Sis currently makes P4 chipsets but they have a poor reputation for compatibility. Via has improved their rep by dominating the Athlon market. They might have the necessary market share to take the P4 platform in directions that Intel doesn't want to go.
The downside is that since VIA don't make motherboards, they rely on mobo manufacturers, and the mobo makers don't want to piss off Intel, and so aren't too quick to look at using unauthorized chipsets.
If no one makes the boards, the chipset may end up more or less stillborn.
If VIA had started with an Athlon chipset, or didn't have this disagreement with Intel over whether or not they're allowed to make P4 chipsets, then there wouldn't be that problem.
However, I would assume that there are obviously some manufacturers making VIA boards, so I would assume those ones would be the ones that would start making boards using this technology.
Advanced users are users too!
VIA -does- make motherboards:
...but they're not exactly considered a 'tier-one' provider.
http://www.viavpsd.com/
http://www.theddrzone.com/news.asp?id=731