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As I understand it, Google disregards any Meta data keywords beyond 155 characters...
For web rankings, Google doesn't use the meta keywords at all. Old myths die hard, but Matt Cutts and Google been very unambiguous about this.
See our earlier discussion, from 2009, in our Google SEO News forum, and watch the Matt Cutts video on the referenced Google Blog article.... Google doesn't use the keywords meta tag in web search http://www.webmasterworld.com/google/3993019.htm
Google relies primarily on visible signals... eg, page title element and page content... and independent inbound links to a page.
When you mention 155 characters, I'm wondering whether you might be thinking about the number of characters Google displays in the "snippet" in the search results. Generally, this snippet is pulled from your meta description, and is limited to roughly 150 characters. The meta description does not affect rankings, but the highlighted terms in a snippet may well affect click-throughs, and a well written meta description for each individual page is worth the effort.
computer support, windows support, router support
Note that to a large extent, even after Panda, the unit of optimization is a page, and in targeting multiple terms like that, you might need individual pages. That said, it's unlikely that you'll get many searches for "router support placename". I would certainly describe all of these services on a Computer Support Placename
page. I wouldn't expect to rank without the placename.