Power = Voltage x Frequency x Capacitance

Chips have capacitance. Tracks on a PCB have a little capacitance. Chip sockets have some capacitance. Connectors have capacitance for each half of the connection. If you can add more and more DIMM sockets, you have some nasty choices:

1) Put some huge power transistors on your CPU (and memory chips) to drive the enormous capacitance of a row of daisy chained DIMM holders - even when few DIMM holders are present.

2) Divide the frequency by the number of DIMM holders daisychained together.

3) Put bus drivers on each DIMM holder (expensive, power hungry and increases the latency)

In short, a modular motherboard is not competitive. A better way to go would be to reduce the number of connectors and sockets. This can be done by putting the DRAM on the same chip has the CPU. Much of the complexity of a CPU is there to deal with the latency of the chip package+chip socket+PCB+another chip package+northbridge+back off the chip package+PCB again+DIMM socket+DIMM PCB+memory chip package. Scrapping all that latency gives you a healthy chunk of space on your CPU for DRAM.

Now your CPU only needs connections for power, cooling and communication.

DC power may not be the best answer. If there was a standard voltage and if you do not mind asphyxiating a few techies when the liquid nitrogen boils, I would say low voltage DC through super conductors. The other choice is high frequency AC. Humans are far more resistant to high voltages at about 1kHz than at 50/60Hz, so you could use thin (expensive) copper cables covered in thick (cheap) PVC carrying a few hundred volts at high frequency without risk of electrocuting people. Converting the voltage only requires a transformer (smaller than you are used to because of the high frequency). Converting to DC still requires a filter, but the capacitors would be smaller than you are used to because of the high frequency.

A nice dream. Google have the income to make it happen, but I do not see them leaping into low margin standards based hardware development at present.

Rack servers did not follow any common standards other than the 19inch rack sizing, and seeing as blade server chassis are usually 19inch that makes them similarly compliant there. PCI, PCI-X and PCI-e came about for interconnects, yes, but everything else like motherbaords was proprietary. The CPUs, RAM and disks were common but they are too on blades. And switches/routers for interconnection were external to the rack servers so could be anything with no promise of commonality (10base-T, 100VG, FDDI, 100Base-T, 1Gb FS, ESCON, etc.). There was no lack of completely proprietary interconnects with rack servers either, such as HP's Hyperfabric.

The real big reason that there are no real standards for blades is because they would stifle innovation. HP and IBM have carved up the market through making blades better than Sun, Dell and smaller players like RLX, by innovation aswell as market muscle. Standardisation too early would have crippled developments like HP's Virtual Connect. In the meantime, lack of standardisation seems to be a very effective Darwinistic means of development - unpopular or innefficient designs just don't get bought.

they are too bloody expensive. I see plenty of blade chassis that don't offer much in the way of density beyond 1U servers and cost 2-3 times as much by the time you've accounted for the chassis and the blades. How many manufacturers individual blades cost more than the equivalent 1U server - for a card that doesn't have a case, power supply, etc. etc. Yes it's more tightly integrated, but in plenty of cases that's done to save money elsewhere anyway. Let's see the manufacturers provide a decent density blade system that saves money on the hardware.

Paris because she's out of my price range too.

massive I/O, fine-grained resource management and scalable CPU power in a box.

Ladies and Gentlemen, I give you... The Mainframe!

Complete with linux virtual machines for standard APIs.

I thought the point of blades was to take cheap, standard hardware used by commodity servers out of its box and pop it in a slot. With all the engineering required for this wishlist in terms of scaling and resource management, the point of the exercise will be missed. I'm not convinced that blades ever promised to be much more than power and space-saving servers with faster, neater connectivity.

Back in the days of the 486, we had multiple vendors using the same socket. Then, they saw competitive advantage to locking users in.

I mean, for example, vendor-specific blade-dedicated switches from Brocade and Cisco? Wtf? *Who cares*?

As for a multi-vendor processor socket: AMD and DIGITAL/DEC (via Samsung, iirc) had that in the days when Alpha was still around - same socket would take an AMD or an Alpha. It was a lovely idea but it didn't take the world by storm - there was and is more to enterprise-class systems than compatible CPU sockets, and non-enterprise customers just want "cheapest to buy, now". Can you really imagine an HP or IBM or even Sun doing the necessary qualification to certify someone else's hardware in their blade boxes? Dell certainly won't.

Don't give me any BS about standards either. The real world knows that conformance to standards doesn't even guarantee interoperability between two products from the same vendor, never mind two different vendors. Lots of things that are seemingly standards based don't work quite right together when push comes to shove; how many enterprise customers are going to want to take that risk, who do they hold to account when it doesn't work (especially if both vendor responses are likely to be "you're on your own, we never qualified your config")?

There are at least two other areas where the "processor independence" track has been tried and failed. They're logically similar although physically different: the NLX motherboard and the PICMG passive backplane concept. In both cases you put the processor and the stuff which needs to be close to it on a plug-in. The slower more remote stuff (eg PCI stuff) is on a separate board or boards. You can still get PICMG kit from various vendors. NLX is afaict dead. The fact that 99.3% of readers will never have heard of these illustrates their historic significance, and as is well known, those who refuse to learn from history are doomed to repeat it.

Then there's the basic physics. Ye canna change the laws of physics, capn, as the comment re volts and Hertz and power duly noted. You want fast, you run hot. No "third way" here.

Summary: Good, fast, cheap. Pick two, and hope for the best.

There's more, but that'll do for now.

AC,

I'm not sure whose blades you've been looking at, but you may want to take a look at Dell's M1000 range..

if you price out a chassis with blades, internal switches, I think you'll find a significant saving over the rack-dense equivalent, not to mention speed of deployment, ease of management advantages.

I can't speak to IBM and HP blades as I don't work for HP/IBM, but typically we've seen them costing as much or more than the rack dense equivalent.

One thing that would help AC is to increase the frequency. At 1khz the transformers can be much smaller and lighter, and somewhat more efficient also.

You don't want to go much higher than 1khz since the inductive losses will sap the power, but while 60Hz is great for overhead power lines, it's a little on the low side for just running power around a data center.