estimating/calculating hash rates for FPGA chips

[CanaryInTheMine]

I seem to remember seeing "back of the napkin" calculations regarding arriving at what a hashing rate would be of a particular fpga/chip.  but I can't find that post anymore...

Can someone point me in the right direction/location for this please?

[fpgaminer]

https://en.bitcoin.it/wiki/Mining_hardware_comparison#FPGA_Devices

[CanaryInTheMine]

https://en.bitcoin.it/wiki/Mining_hardware_comparison#FPGA_Devices

  thanks!  I'm very familiar with this page

I was thinking along these lines:

if I take x number of some fpga chips, assume a bunch of other things, here's how to do a rough estimate on the expected hashing rate....  That's what I'm after.  I can't find that post...

[fpgaminer]

if I take x number of some fpga chips, assume a bunch of other things, here's how to do a rough estimate on the expected hashing rate....  That's what I'm after.  I can't find that post...

It's easiest to do with Altera Cyclone chips, and roughly works out to:

1,000 LEs = 1MH/s

Could be more in some cases, less in others, but that's a fairly good baseline. For Spartan-6 it's roughly:

1,000 LEs = 0.5MH/s

For high-performance families like Virtex or Stratix you should multiply by 3 or 4.