Re: partially unrolled?
Martin Klingensmith <[email protected]> Tue, 28 Nov 2006 08:08:34 -0500
| Newsgroups | gmane.comp.distributed-net.hardware |
|---|---|
| Message-ID | <[email protected]> |
John, With my incomplete core IIRC I was unable to get it to fit on any Spartan 3 device. Can something be hand-optimized to be significantly smaller? Also, I was unable to find a place that had the XC3S2000 in stock. Direct from Xilinx? -- Martin K John L. Bass wrote: > ABC> I read on this list that a fully unrolled design is too large for any > ABC> FPGAs we can afford, while a fully iterated is probably too slow to be > ABC> useful. > > Hi Guys, > > I did some poking around at Xilinx FPGA pricing for devices big enough to > handle a fully unrolled pipelined design, and found that Spartan-3 devices > are pretty affordable and have enough features to realistically support a > standard Dnet design. > > XC3S2000 devices are just under $100/each, which means it would be practical > to design a very low end PCI card that supported up to 8 of these devices. > > With some pruning, I suspect that we might also be able to fit the core into > an XC3S1500 device which are price about $75/each in hundreds. > > The XC3S1500 device has the added benefit that it's supported by the free > web pack tools, meaning that hobbiests would not have to invest in the > $2K Xilinx ISE tools to use their accelerator board. > > I suspect the performance will be near that of the Virtex-4 devices, and > much better on a MegaKey/Sec per Dollar scale. > > Guerric should have better numbers in a day or two, and we are collaborating > on improvements and strategies, off list. > > Both of these devices would make practical general purpose FPGA computing > engines using available C compilers, as well as traditional VHDL/Verilog > designs. Using low overhead production, boards priced between $150 for a > single FPGA and about a grand fully loaded are very possible. If done > commercially, they would have to carry a 2x or 3x markup to cover other > costs. > > The parts are only available in fine pitched BGA, which will increase board > costs slightly due to the small vias required and extra tight layer to layer > layup error management. There is a lead-free program for the parts, so we > can be environmentally friendly too. > > ---------- > > Can someone post what the Dnet core counting sequence, work assignments, > and work checking requirements are for a valid DNet core to participate? > > I'd like to work with Guerric to get a functional first pass core running > on silicon just to validate the design and do some power/thermal testing. > > Have Fun, > John > _______________________________________________ > Hardware mailing list > Hardware-Ra3b/QYEcJ3d140v2zMXi0fjHoOT/h/[email protected] > http://lists.distributed.net/mailman/listinfo/hardware > _______________________________________________ Hardware mailing list Hardware-Ra3b/QYEcJ3d140v2zMXi0fjHoOT/h/[email protected] http://lists.distributed.net/mailman/listinfo/hardware