Dear Yingwenlaoshi,
I think that, in essence, the two sentences mean the same thing.
In "A Comprehensive Grammar of the English Language" (2010), by Professor R. Quirk and others, they write regarding several subordinators, including �as soon as�.
They indicate that, when using the subordinator in the Subordinate Clause, there is often a choice between using the Present Tense OR the Perfect Tense.
The meanings are �roughly the same�.
They imply that the Present Tense is �more commonly used� than the Perfect Tense.
They write:
The Present Tense in adverbial and nominal clauses (page 1008)
The Simple Present is commonly used in certain types of adverbial clauses to express future meaning.
... ...
As soon as he arrives, the band will play the National Anthem.
The Perfective with Other Temporal Clauses (pages 2018-2019)
... ...
The Present Perfective is common in temporal as well as conditional clauses for a future event referred to in the matrix clause ... ...
As soon as I�ve retired, I�ll buy a cottage in the country.
------------------------------------------------------
On a personal note, when I read your two sentences:
1) As soon as he opens the safe we will be able to take all the money.
2) As soon as he has opened the safe we will be able to take all the money.
In 1), I imagine that �we� are approching the safe, confident that it will be open soon.
In 2), I imagine that �he� has been trying to open the safe for the past few minutes, but that it will be open soon.
I am sure that other Members will have have other ideas.
However, I repeat, broadly speaking, the two sentences mean the same thing.
I hope that I have helped you.
Очень рад!
Les
