> I am not insist on 7457 with Sonnet 1.8 GHz single.

I know :-) I just want to explain myself why I'm confident that the lowendmac.com list is incorrect in this regard. Feel free to ignore my ramblings if you don't find them interesting or useful.

> I just looking for real info about overclocked 7457 VCore. Information
> if Sonnet had 7447 or 7457 is redundant for this question.

Not quite, I think. If Sonnet really used 7457 CPUs overclocked up to 1.8 GHz, the info you're seeking may be derivable somehow from (preferably non-destructively) examining such Sonnet card. If they didn't, they are not.

>> I'm with you that in the case of the Sonnet Encore/ST G4 cards,
>> 745x comes with L3 cache deployed.

> 7457 can be connected without L3 cache. [...]
> But it makes no big sense in case of Sonnet

Yes, absolutely.

> 7447 had these times higher default frequency

I'm not sure what "default frequency" means here, but yes, in terms of maximum rated frequency, during the first year, the 7457 was 1267 MHz vs. 1300 MHz of 7447. After that, the 7447 got downrated to 1267 MHz as well. This happened around 03/2004.