Dear Professor Andrew Eckford,The messages are so similar, both in terms of content and geographic origin, that I have to think there is some agency behind them. But particularly because they are so similar, it's easy to dismiss them as spam and ignore them. It probably doesn't hurt an applicant to send these emails, but I would never remember such a message at admission time, so it certainly doesn't help either.
I saw your web page and am very interested in your research on computer networks. I have the same research interests as you and would like to apply for a PhD position under your supervision. My master's thesis was entitled "[topic I'm not interested in]" and I published my results in [conference/journal I've never heard of]. I am attaching my resume to this email and look forward to your positive reply.
What would get my attention is an applicant who makes it clear that s/he is not just interested in the PhD slot. In fact it's probably unnecessary to mention in the first email that you're a Ph.D. applicant; what I really want are bright students who are interested in research in general, and my research in particular. I've never received an email like this from an applicant, but I would certainly remember it if I did:
Dear Professor, I read your recent papers on fractional cooperation, and thought the idea was interesting. I have the following comments and questions about your scheme ... [some insightful commentary follows].Of course, a more personal touch works for me, because my group is small and I can afford to be very selective with my Ph.D. applicants. Maybe the form letter approach works for profs whose groups are measured in the dozens.