I have a long in the tooth white 2.16 24 in C2D iMac with the expected video card issues. My question is for the techies - would reverting to Leopard from Lion help prolong the life of the machine as a whole? I am betting not but I am betting the current OSes are not helping the video board. It is having mini freezes where it appears to be "restart" the video and runs fine then recycles this behavior. I know it is long in the tooth and have received a cost to replace the board but just trying to stretch out the machine for a little longer.

I have a long in the tooth white 2.16 24 in C2D iMac with the expected video card issues. My question is for the techies - would reverting to Leopard from Lion help prolong the life of the machine as a whole? I am betting not but I am betting the current OSes are not helping the video board. It is having mini freezes where it appears to be "restart" the video and runs fine then recycles this behavior. I know it is long in the tooth and have received a cost to replace the board but just trying to stretch out the machine for a little longer.

Considering the extra resources that Lion 10.7.x uses, your logic makes sense and SL may be a better less resource intense OS option to use.

Regardless, I would suggest installing one of the compatible "Fan Controllers" as the plastic case units especially, and even the later aluminum case iMacs need better cooling than Apple default.

I use 'Fan Control' with my 24" 2.4GHz iMac whether I'm booted in SL (my default and preferred OS X) or Lion or ML which is even more resource intense but your iMac can't normally use ML.

It might get you some more time and relieve some heat stress.

Download Fan Control for Mac - Hassle-free fan speed manager for MacBooks. MacUpdate.com (http://www.macupdate.com/app/mac/23137/fan-control)
or
Lobotomo Software: MoofMenu (http://www.lobotomo.com/products/FanControl/)

Mine is in 32bit only because of some other old pref pane.

its doubtful that rolling back would "fix" the issue. you might see it less, but itll still be there

its doubtful that rolling back would "fix" the issue. you might see it less, but itll still be there

Is the old Apple extended warranty still in effect for the Nvidea video problem if such Macs were even affected?

I know I just got under their time frame wire with my mid-2007 2.2GHz MBPro last Sept. 2011 for a full logic board replacement, but it wasn't just flakey, it wouldn't even boot properly and nothing but a solid black screen.

But it's still all working well now thanks to a local authorized Apple tech's extra support to get it replaced via Apple's extended warranty support.

Is the old Apple extended warranty still in effect for the Nvidea video problem if such Macs were even affected?

The OP has an iMac.

The OP has an iMac.

So I gather that the extended video warranty for the Nvidea video problem was not associated with any iMac, but for MBPros only?

I thought some iMacs were also included but my brain's recall is failing me. ;)

I thought I would update anyone who is interested in the completion of this project.

Since August I decided to move the OS back in time to try and save this machine. It was loaded with Lion and I wanted to install any of Tiger, Leopard or Snow Leopard. All retail DVDs would all mount but not install. Some would allow hard drive formatting but even after any OS formatting using OS specific Disk Utility, the Rescue "disk" from Lion would still be available and never mounted. It would be present as a Startup Disk choice but was not present during any session in Disk Utility, noting that any version of Disk Utility from Tiger, Leopard or Now Leopard could not "see" this Lion created disk.

So I took the challenge and bought a new HD and found a replacement 256MB video card. I originally installed the HD and verified the ability to install and update as wanted and once at this position, I then changed out the video card. Everything installed just fine and now I am at Snow Leopard with a fairly spiffy machine working on getting Time Machine ready to reload the contents. Thanks to all who helped with their comments.

You should be able to blow away the Recovery partition with a new partition/format and write zeroes if needed on that HD to recover ALL the space.

Otherwise if you have a means to assess it from a working Mac, an install disk can't be modified of course, you can add the "Debug" 'Developers Tools' to Disk Utility and select "Show every partition" from the DU menu.

Enable Hidden Secrets and The Debug Menu In Disk Utility [OS X Tips] | Cult of Mac (http://www.cultofmac.com/122623/enable-hidden-secrets-and-the-debug-menu-in-disk-utility-os-x-tips/)

Enable Disk Utility's Debug Menu (http://macs.about.com/od/usingyourmac/qt/Enable-Disk-Utilitys-Debug-Menu.htm)

etc.