How relevant are non-top conference papers to a PhD CS admit panel? (USA) Background:
While I am not sure about other fields, Computer science has several conferences an year for multiple of its domain. (there are around 150+ conferences for artificial intelligence alone). Out of all of these conferences, only 15-25 are actually highly regarded and considered as A to A* category.
The other conferences while good, are not really known. They have good proceedings like springer LNCS, ieee explore, etc. They also hold sessions conducted by profs from top schools and people from top private RnD labs. Few even allow the extension of the paper to be accepted into transactions.
Apart from these, there are always the top journals which are SCI indexed.
Question:

Do accepted papers from the non-top conferences add any value to an undergrad CV applying for PhD schools?

Additional motivation for the question:
The alternative to not publishing is keeping it as a pre-print or just a softcopy to link in the CV. But I am told in another question that some form of peer review always adds some weightage. Hence the question.
Let's assume a paper in a B conference. In the CORE system, from which the division into A*/A/B/C stems, B conferences are literally called &quot;good to very good&quot;. A publication in a B conference is a nice CV entry and definitely valuable. How valuable might depend on the particular conference, as not everybody shares the same opinion about all conferences. Ranking decisions of the CORE committee certainly have been disputed in the past. In my area, there are fairly good conferences which have not even been ranked by CORE, despite being organized by top researchers and being around for more than 15 years.
But it will also depend on the subfield of CS. There are particular &quot;hot&quot; subfields that have crazy expectations about a PhD applicant's research profile. There is an interesting blog entry from someone who published at an A* conference in AI as an independent researcher to get a PhD position (and ultimately does not recommend anyone to follow that path). Another BSc graduate with a B conference paper might have a hard time competing against that.