Seems suspicious to me, considering the Radeon x1900 had a recall program on it. Not sure if it still does or not, but screen freezes and no display are definitely classic symptoms of the x1900.
If this was an Apple retail store you went to, take it back and tell them to look this up, or to go in the back and talk to a TEA about it. If it was a third party repair place, then it sounds like either they are just guessing or trying to pad the bill. Or both.
I can't remember if the x1900 recall program is still going on or not, I'd have to go look and I'm running a bit late, but considering you bought a pretty high end unit back in the day, and they were morons who likely gave you a WAG of a diagnosis, you probably have a decent chance of them eating the cost of the repair just to keep you from making the scene you're completely justified in making. As I recall, they replace it with the nVidia GeForce 8600, which is actually a bit quieter as I recall.
I'm very dubious about the MLB diagnosis here though, so if you were ever given some sort of a case number, if you post that here I can get someone to send me the tech's notes for your unit and find out whether or not they're full of it.
I have a 2.66GHz MacPro Quad Core, Apple installed RAM, 1 x 500GB HDD, 3 x 320GB HDD, Apple upgraded Graphics Card ATI x 1900xt. 2 x Superdrives installed 16x write speed, DVD/CD R/RW. Lion installed. It's probably 5/6 years old, configuration cost almost $5,000.
Since recently upgrading to Lion OSX 10.7.2 from Snow Leopard I have had continuousScreen Freezes, Screen Going Black, or Beach Ball just spinning non stop. This can happen as often as 10 or 15 times in 30 minutes, regardless of programme that's open or in use at the time. With Snow Leopard I did get the very occasional screen freeze. I have run Disk Warrior a couple times and it repaired any faults it found.
At one stage on boot up with Lion installed it went as far as the white screen, and that was it, it would boot no further. I took the machine into my local Apple Service Centre. One problem they diagnosed was a faulty Logic Board, which they said may result in reduction of colours, and a couple of other things they mentioned, cost of new LB $1200. They got everything working again but advised against installing a new Logic Board due to the age of the machine. I'm very reluctant to lay out the cost of buying a new Mac to these specs'. Is it probable that a new Logic Board would resolve the issues or am I still likely to have problems? Is a 5 or 6 year old machine considered a throw away item, or is the problem with Lion itself? I twice carried out a re-installation of Lion. Any advice would be appreciated.
bryanall
Note: This post was edited by a forum moderator to remove unintended HTML codes in post on 01/06/2012 at 11:45 AM PT

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