Older MacPro (1,1 2006) concerned about installing Lion

Stay with Snow Leopard unless you have Lion compatible updates for any of the hardware drivers installed by your third-party hardware/software products. Any pre-Lion third-party software may also require upgrades for Lion compatibility. You will need to research this before making a decision.

Or you can install Lion on a separate drive partition and check things out for yourself without disturbing your Snow Leopard system.

dupe. ignore.

I have a system similar to yours in specs (same generation, same memory, similar other stuff) without the specialy PCI cards. LION works well. Nothing improved my system as much as swapping my boot drive to a SSD drive back when still on 10.6. I will second the motion of putting it on a separate drive and trying out your apps and hardware. If you don't see a compelling reason, wait before going live with it - at the current price you can afford the experiment.

Works just fine on my Mac Pro and six other Macs I own plus two belonging to my daughter and son-in-law.

I'm afraid you're being sucked in by the rumor sites and local complainers. However, I certainly concur that if you don't need Lion then there's no need to upgrade.

From 10.3.0 to now, I consider every new release version with the zot zero and even dot ones, to be nothing more than final candidate or release candidate quality and rushed or pre-mature.

With dot two now, and required of all things for iOS 5 (which also requires 10.5.0 which has its own set of issues)

The lack of PowerPC meant that the code could be optimized and cleaned, and reduced the footprint to some extent.

Lion Recovery, net install and also net hardware test, also is nice but very much 'tethered' to the mothership.

5345s are popular sub $500 way to get 8-core 2.66 out of those 1,1s too, and there is an unofficial firmware update 2,1 for those interested.

Intel: their public roadmap and announcements and what isn't yet but will become available, and interdependent: PCI Express 3.0 with more bandwidth and support for SATA 6G for one thing and to tab Thunderbolt for PCs (helping drive down costs). We need SATA3 2GB to replace the 6 yr old SATA chips (the MacPro 1,1 firmware etc were born a year before it saw the light of day, 2005 while the Late 2005 G5 was itself being sent thru assembly and manufacturing).

LGA2011 Ivy Bridge - a must would bring 6 and 8-core processors with higher performance has been requiring longer and more work and testing by Intel to get yields and performance. Plus beginning work on DDR4 has started. DDR3 took memory bandwidth from 8GB to 24-32GB/sec depending on motherboard configuration and BIOS, so I would guess DDR4 will take it up another notch as well - by 2014.

All in due time, if iPad 5 w/ A20 and quad-core @ 2.2GHz doesn't crush it! :-)

Stay put is my advise unless you have a newer model mac!

I just recently upgraded to Lion and there is a performance drop in Logic pro 9.1.6.

It does not respond as fast as usual and it's extremely frustrating to your workflow.You'll clcik to open the EQ then while playin gtrack you wanna gain up a frequency and logic will take its sweet time to resond and then all of a sudden it does and the EQ shoots up to the top because of the delayed message. Also experiencing a delay with stopping while playing and a delay in closing plugs, it doesnt occur emmediately but once you get about 70-80% of your proccessor useage. Under SL this did not happen. Diffinite delay.

I also own a Mac Pro 1,1 but my processor speed is a bit slower, 2,6Ghz X4 core with 9Gig ram. I'm planning to downgrade back to snow leopard cause it irrtates the living **** out of me.