Lets not forget, this partnership happened over three years ago. Yahoo search has been "powered by" HP for quite some time now. I believe this predates Google's partnership with Dell (not to be confused with a sponsorship, which is what the Dell/Google portal represents) by quite a bit.

The Google/Dell deal is a bit different. There is a partnership, but it is not directly in terms of the core search engine. Although they have various agreements about Google software being included on Dell products and Dell manufactures the hardware for some Google products, Dell does not have a hand in Google's search algorithms.

The Yahoo partnership with hp is somewhat different. In that partnership, HP provided certain technologies that were incorporated into Yahoo's search capabilities. However, it is interesting to note that that partnership seems to have ended, with HP partnering with Microsoft Live Search in 2007.

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