We recently covered IBM's iron grip on server revenues. However, if you look at units shipped, the picture is very different -- showing unit share leader HP locked in battle with IBM for unit share, revenue share -- and mindshare.

Overall, the worldwide server market grew 8.1 per cent annually to $12.5 billion in the third quarter, according to last week's report from market researcher IDC. While Big Blue leads in both blade and rack servers, it's only in third place by units shipped, behind HP and Dell for the same period, although both IBM and Dell increased their shares slightly at the expense of unit share leader HP.

And while Big Blue also leads in overall Linux-based server revenue, in the x86 space generally, HP is top dog, and experienced year-over-year revenue growth of 22.7 per cent, with a good showing in x86 blades, up 64.9 per cent. The x86-based server market shares mirror the overall server share positions which is hardly surprising given that x86 servers constitute over 90 per cent of all servers shipped. In a distant fourth spot behind HP, Dell and IBM is Fujitsu Siemens, followed by Groupe Bull.

However, there's a lot of vendors with small shares in the x86-based market: after the top five, the rest sell almost as many servers between them as does top-spotted HP, although their growth rate wasn't quite as high as HP's. It was greater than both Dell's and IBM's though, suggesting that, despite the big vendors' claims to want to talk to and sell to SMEs, they're not making much headway.

Unix servers
This is a hard fought-for market. While the numbers involved are very low, the money that each unit commands, and the prestige that goes with researching, developing and producing high-end servers brings a halo effect to lower-end products. IBM's doing well in this area, increasing its share with 29.4 per cent of the market, up by 11.1 per cent in the last year.

However, Sun Microsystems easily maintains its unit share leadership in this market, although its downward trend continues, down to 57.77 per cent compared 59.87 per cent compared to the same period last year -- that represents sales of almost 6,000 servers -- while IBM's continues to grow in second spot -- it's up from 21.35 per cent to 23.33 per cent. HP is in third place but is losing share slightly -- down from 14.81 per cent to 14.45 per cent, according to Gartner. This may be due to its continuing emphasis on Intel Itanium, whose sales are broadly flat, compared to IBM's broader product offering, with both Itanium and its own Power chip-based products. However, the picture's not as clear as it might be: HP claims large growth, quoting IDC's report showing its Itanium-based servers up 74.6 per cent.