What is the earliest time for psukei dzimra? Rashi says that yishtabach can be said before zman krias shema. But while berachos can be said much earlier because that is ties to the person waking- psukei dzimra has a shaychus to shachris. Would alos be the earliest? Does that mean if one had to daven early (bedieved) he would not say any psukei dzimra.
Moshe Rubin, Brooklyn, NY
It seems to be a Machlokes Poskim ha'Achronim. The Sha'arei Teshuvah (664:1) quotes the Maharil who says that he once declared a fast because the Kehilah mistakenly put on Talis and Tefilin and said Pesukei d'Zimra before Alos ha'Shachar. On the other hand, the Sefer Da'as Torah (ibid.) argues and says that Pesukei d'Zimra may be said before Alos ha'Shachar, and he brings as his proof the Rashi that you mentioned (Berachos 11b, DH Yotzer). It is not clear, however, what his proof is from this Rashi, because Rashi says only that one may say Yishtabach before Z'man Keri'as Shema.
Perhaps it is implied in the Shulchan Aruch itself that one may say Pesukei d'Zimra before Alos ha'Shachar. The Shulchan Aruch (OC 58:3) says that when one is traveling in a caravan and the caravan won't wait for him, he may say Keri'as Shema and the Berachos right after Alos ha'Shachar (and not wait until "Ad she'Yakir"). Presumably, in such a case he may say Pesukei d'Zimra beforehand which means he is saying it before Alos ha'Shachar.
It is worth pointing out that Rashi (Berachos 11b, last Rashi) says that the second Berachah of Keri'as Shema -- Ahavah Rabah -- may be said at night before dawn. This certainly would suggest that Pesukei d'Zimra could be said while still night. Keri'as Shema itself must be Z'man Kimah, and Yotzer Or must be at a time when there is some light. But Pesukei d'Zimra has no such limitations.
This is not a Psak Halachah