Office Crashes G5 with replaced ATI X800XT

I'll try and be succinct with an amazing array of "coincidences".
G5 dual 2 ghz, 6 gig RAM Leopard 10.5.8. All programmes are "kosher" bought from proper retailer. Mac was bought brand new from Apple reseller.
So all was working well until December 2010. The ATI 9600XT that was factory installed at purchase, went down and a red "grid" was on both screens and so had had it's day. These are no longer made and the only used card I could find was an ATI X800XT 256meg on board.

This worked well, but I noticed that when I tried to start "Word" the machine would sleep, I pressed a key and it burst back to life, for 8 seconds and then slept, again and once more. I shut it down, left it for a while and restarted, then I had a message about a disk insertion that couldn't be read, so I pressed eject and on I went, all worked fine until I received a doc file and when it tried to open, SLEEP, it was like a hypnotist, open and Office programme and SLEEP. I zapped PRAM, repaired disk permissions, rebuilt with DiscWarrior and still had problems starting and always this sleep or disk insertion message.
I rang the local Authorised Centre and I took their advice and re-installed Leopard. PERFECT no start up hangups no problems, until I tried to open an office Doc (any office progamme). I uninstalled Office with CleanMyMac. Tried to re installed M.Office. As soon as I double clicked the Disk, SLEEP hypnotist is back, but now the second screen via ADC doesn't work. Shut down. Went to restart about 2 hours later with only the DVI 23" Cinema Display, no power whatsoever. Reset the PMS and it started, until I connected the ADC Formac screen, not just sleep, crashed to a no power state. Restarted with an old ADC monitor and all is well now. can't use Office at all, I even downloaded another notsokosher Office, as soon as I opened the Disk Image, SLEEP. Tried the kosher version, SLEEP. Threw away Microsoft Office and now use Open Office and all for the last week is well.
I can't find any correlation anywhere about compatibilty problems between the ATI Card and Microsoft Office, and is it all the Sleep and restarts that's blown the Formac ADC monitor? Sorry to go on,but as I paid a couple of hundred pound for a proper Microsoft Office, it's a bit off that it won't work. But hey, Open Office does. Or is the ATI RAdeon vs M.Office a red herring, is there a nonexistent tree up which I have been barking? Only you would know and if you do I'd appreciate an idea or 2. Sorry this has gone on but it was a complicated issue, well for my limited expertise anyway. thanks for your time, Slotype.

Clean my Mac? Give ikt a big miss and use Onyx.

http://www.mac-forums.com/forums/os...-mac-utilities-mackeeper-vs-clean-my-mac.html

Have to use the genuine uninstaller to remove Office. And have used that card with Office 2008 no problems.

Thanks very much, so you think it's the remnant of Office that gave me grief? It was all working OK before the card went in. OK how do I find the odd files to get rid of them, or if I get Onyx will that find 'em for me? Really appreciate everyone's help. I need to do something before I try to reinstall, although Open Office seems to work OK at the moment.

As the original card is AGP, wondering if the X800XT is a Mac compatible card, and if only for PCI-E computers only?

Thanks again. The X800XT card IS a Mac edition and all is settled down since I started Open Office. I had a Formac ADC monitor which has given up the ghost since the aggro and if I try and connect that, all goes bad, but an old low res ADC monitor from a Cube (Ahh takes me back) although low res, work fine. I'll just save for a new Mac I think. Appreciate all your help