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So, Is it possible to upgrade leopard 10.5.8 to mountain lion 10.8 without paying snow leopard or lion?
In a word, no.
Today Mountain Lion OS X 10.8 is only available as a download from the Mac App Store for $20.
To get the Mac App Store, you must purchase a $25 (price you were quoted) Snow Leopard OS X upgrade on disc, and update it to 10.6.6, or later.
Total Cost $45.
OS X 10.7 Lion was originally released as a download-only from the Mac App Store for $30. (Still requires Snow Leopard 10.6.6 or later - you were quoted $25.) to upgrade to Snow Leopard then Lion and stay on Lion OS X 10.7 for the moment.
Total cost = $55.
OS X 10.7 Lion was eventually released on a flash drive at $70 (versus $30 download-only price.)
So you could buy the Lion upgrade and remain on that version without purchasing Snow Leopard. "Savings" from not purchasing Snow Leopard = $25
Total Cost = $70.
Or you could buy the Lion flash drive and then you could download Mountain Lion.
Total Cost = $90.
Today, just a week after introduction of OS X 10.8, Apple has not announced Mountain Lion availability on a flash drive.
They could eventually, but there's no way of knowing at this point. We're not employees here, just users like yourself.
So if you don't need to upgrade right away, wait a while to see what happens.
Recent OS X upgrades are still a 'deal', even if the Snow Leopard upgrade just sits on the shelf and collects dust after being used for an hour during installation, and then never again.
To fully appreciate the low price of Apple OS upgrades, compare them to Windows upgrades:
$25 for a Snow Leopard upgrade plus $20 for Mountain Lion together are still only about half the $90 street price of a Windows 7 upgrade from a prior version. Windows 7 upgrades had a $120 list price when first issued in 2009. Windows 8 will debut in October, and that upgrade cost is rumored to be $40.
I'd also suggest a RAM upgrade to at least 4GB (and 6GB or even 8GB RAM if your system supports it) to boost overall Lion or Mountain Lion performance. Check RAM upgrade prices from reliable vendors of Apple-compatible RAM such as Crucial.com and Other World Computing (www.macsales.com).
Message was edited by: kostby