In our annual enterprise IT infrastructure decision-maker survey, we asked firms what server vendors they'd been customers of in the previous 12 months. We analyzed responses in detail to get beyond the simple observation that HP and Dell lead the market overall and learned that 78% of firms buy from more than one server vendor. A full 49% of respondents buy from both Dell and HP, while 40% buy from HP and IBM. When we analyzed each vendor by customer base, we learned that nearly half of HP's accounts are either exclusive or with only one other vendor and that IBM and Sun Microsystems are more likely to have accounts with three or four server vendors than either Dell or HP.