Does the A5 version of a MAX V have different timing than an I5?

Calvin,

Can you (or someone else) explain why my customer (and I) get different results from TimeQuest depending on whether we choose an I5 or an A5 device? I would think that Quartus would provide the exact same place and route. However, when the customer compiled the same design for 4 different MAX V 570 devices (different speed grade/temp range) here are his results:

I took the design and compiled it under the 4 different speed grades and looked at FMax. From what I can tell the I5/C5 have same timing, A5 is faster, and C4 is fastest. I know that they keep implying that the A5 is just a "binned" I5/C5 but that is certainly not what the Timing Analyzer seems to be reporting.

FMAX: A5 C4 C5 I5

-------------- ----------- ----------- - ---------- -----------

smclk (24MHz): 30.24 MHz 51.1 MHz 25.48 MHz 25.48 MHz

lclk (66MHz): 65.33 MHz 128.5 MHz 65.33 MHz 65.33 MHz

Steve