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Comments on: SiCortex sticks to Summer supercomputer ship

milli-kilo-mega 

Posted Thursday 21st June 2007 19:30 GMT

How does the math work? (10W/chip)*(27 chips)*(972slap-togethers) = 262440W = 262kW (kW = kilo-Watt = 1000W). Is there some option to slow the beast down and then consume 600mW (mW = milli-Watt = 0.001 W)? Comes close to a perpetuum mobile... Please be careful about the math and the units!

someone got the numbers wrong 

Posted Thursday 21st June 2007 22:16 GMT

According to SiCorex website, SC5832 "offers 5832 1GFlops 64-bit processors, each dissipating just 600 milliwatts of power". There are indeed 27 chips on a board, and it seems like one chassis contains 26 such boards, so we have: 6 (cores) * 27 (chips) * 36 (boards) = 5832 CPUs. It also seems that one can connect two or more of those machines. I/O controllers including two DDR-2, PCI Express and fabric (the one that interconnects all CPUs) are embedded into a chip. Each board seems to offer 3 PCI Express running at 20Gbps available to the outside world (or another SC5832).

Holds Head in Shame 

Posted Thursday 21st June 2007 22:59 GMT

(Written by Reg staff.)

Sincere apologies there. Mucked up those numbers. Have fixed story. Thanks for that, fellas.

AV

www.theduckrabbit.com

Filling in the numbers 

Posted Friday 22nd June 2007 13:16 GMT

Ashlee -- sorry about any confusion we may have caused on our end.

To repeat the numbers:

We've done the engineering necessary to keep the power low. We started out with an engineering budget of about 15 per node (node chip + 2 DIMMs). The node chip aimed at 10W, the rest allocated to the DIMMs. Add to that the overhead for power supply and conversion losses and you get about 18W from the wall for each node.

The 648 processor systems that we've built are measuring about 1500W from the wall running real workloads. That says that the actual node power is below our engineering budget.

So, the math again is

SC648:

6 processors per node

27 nodes per module

4 modules in a system

4 modules * 27 nodes/module = 108 nodes

108 nodes * 18 W/node = 1944W

SC5832:

6 processors per node

27 nodes per module

36 modules in a system

36 modules * 27 nodes/module = 972 nodes

972 nodes * 18 W/node = 17496W