what info will be lost by uping to OSX

Nothing will be lost but I would do a backup before hand 'cause you never know.

You MUST back up your files, or you can expect to lose then -- even running Snow Leopard!!!

Once you have a backup, then we can talk.

You should not lose any files, songs, photos or data: a standard install of Mavericks replaces the old OS, leaving all your data in place.

The only risk is in making sure that all your apps will work properly in MAvericks. Some will need updates; some will require new versions; and some won't work at all, depending on what you have.

Obviously, Apple's own stuff and stuff in the App Store will be up-to-date. You'll need to check with the makers of your apps to see if their software is compatible with Mavericks. The older the software, the less likely it will work.

If you run any older Mac software from the earlier PowerPC Macs, then none of this software will work with the newer OS X versions (10.7 and onward). OS X Snow Leopard had a magical and invisible PowerPC emulation application, called Rosetta, that worked seamlessly in the background that still allowed older PowerPC coded software to still operate in a Intel CPU Mac.

The use of Rosetta ended with OS X Snow Leopard as the Rosetta application was licensed to Apple from a company which got bought out, I believe by Micrsoft and Appe could no longer secure their rights to continue to use Rosetta in later versions of OS X.

So, you would need to check to see if you have software on your Mac that maybe older than, say, 2006 or older.

Also, make sure your Mac meets ALL OS X minimum hardware/software upgrade eligibility requirements.

OS X Lion system requirements

To use Lion, make sure your computer has the following:

• An Intel Core 2 Duo, Core i3, Core i5, Core i7, or Xeon processor
• Mac OS X v10.6.6 or later to install via the Mac App Store (v10.6.8 recommended)
• 7 GB of available disk space
• 2 GB of RAM

To install Mavericks, you need one of these Macs:

• iMac (Mid-2007 or later)
• MacBook (13-inch Aluminum, Late 2008), (13-inch, Early 2009 or later)
• MacBook Pro (13-inch, Mid-2009 or later),
• MacBook Pro (15-inch or 17-inch, Mid/Late 2007 or later)
• MacBook Air (Late 2008 or later)
• Mac mini (Early 2009 or later)
• Mac Pro (Early 2008 or later)
• Xserve (Early 2009)

Your Mac also needs:

• OS X Mountain Lion, Lion, or Snow Leopard v10.6.8 already installed
• 2 GB or more of memory
• 8 GB or more of available space

Also, check for app compatibilty here.

http://roaringapps.com/

Good Luck!

See this tip to ensure everything is compatible:

https://discussions.apple.com/docs/DOC-6271

ken kirk wrote:

What info (songs, photos, games, etc) will be lost by up grading to OSX from 10.6.8 Leopard?

As discussed in more detail by MichelPM, most of your games will probably not run in Mavericks due to the lack of Rosetta. Consider this upgrade strategy:

Of course, backup or clone first.

Partition your hard drive or add an external drive and install Mavericks there. DO NOT install Mavericks over Snow Leopard, as that will destroy your Snow Leopard environment.

Use the dual-boot method (System Preferences:Startup Disk) to determine when you boot which flavor of OS X you will boot and run: Snow Leopard or Mavericks.

Experiment with your applications and games in Mavericks. Those that do not work, see if there are upgrades available. Those that do not work and have no available upgrades, boot into Snow Leopard and play them there.