I?m hopeful that this is in fact the problem, and its not a case of something more serious (either RAM or mother board failure).

Having now done 2 clean installs onto the MacPro both of which have a similar problem of display corruption when scrolling and performing random functions.

This problem started to appear just after the EFI update went onto my Mac Pro last month, and has become worse having installed 10.5. In fact, booting back into 10.4 the problem is hardly noticeable but can be seen when you look for it.

On 10.5 its very very noticeable However when I try and take a screen shot of the problem it seems to clear up – as though a redraw happens which removes the corruption.

Being even more stupid? (brave!) I went for the upgrade option instead of the customary Archive and Install.

To my surprise it worked well, and within no time I had Leopard running on my Mac Book Pro. Now all the way through the beta programs I?ve had 10.5 betas installed on the MBP and then removed them and went back to 10.4 because of compatibility issues with things like my XU870 3G data card, and some weird hangs with Mail.app and so on.

Much to my surprise (dismay), Mail.app still hangs .. but no-where near as often … and after some fiddling I managed to get the Novatel XU870 card working with the built in drivers, and so don?t need to worry about waiting for 10.5 specific drivers to be made available from Novatel (woohoo)

Next came the upgrade of my media centre (mac mini) from 10.4 to 10.5 .. that too went remarkably smoothly and happened in no time. And I can now watch DVD folders straight from within Front Row – excellent! The Kiss DP-1600 is well and truly consigned to Silicon Heaven (bids accepted for that brief encounter with media centres – I certainly won?t be keeping it!)

Then came the problem … 6 hours spent (wasted) trying to get 10.5 to install (boot even) on my Mac Pro (Dual Core Dual Xeon 3Ghz) … would it go past the language selection on the first screen? Most of the time it wouldn?t even get THAT FAR!

Microsoft has the last laugh!

Eventually, I managed to track the problem down to what would appear to be a conflict between my Microsoft cordless mouse and Leopard. Unplugging the mouse meant the installer booted fine. Down side was that all of my spare Apple mice are in storage … but some fiddling and tinkering with Bluetooth mice eventually meant that I was able to get something jerry rigged and we were off!

More to follow

I?ll post more tomorrow, once the data migration (370Gb of data!) has completed on the Mac Pro, and I?ve had more of a chance to test the final release version of Leopard. Initial impressions are however that it?s much more stable than any of the betas we?ve been privvy to over the last 3-4 (6?) months, and with the exception of a few last minute ?surprises? on the whole its as was released in October as the ?ZBB? version.