"I purchased a Power Mac G5 Quad (2.5 Ghz with the Delphi LCS) back in December of 2005 along with an AppleCare warranty. (So it's still under warranty then?-Mike) Not sure if I had a leak, but CPU Temps on Processor B were consistently a lot higher than processor A by on average 50celsius (this started around November 2007). I usually use this machine for Aperture, Adobe PS, and also as my World of Warcraft machine. About a month later (December 2007) I started experiencing random forced sleeps (sleep or shutdown?) along with a red LED visible from the front whenever playing WoW or using Photoshop. I opened the box up and checked for leakage or signs thereof and wasn't able to find anything.

I brought my Power Mac into the Apple Store after making an appointment in early January and after a preliminary check (and my showing them excerpts from my system log showing thermal runaway and stats) (system log entries on "PMU forced shutdown, cause = -122" and/or "thermal runaway" messages were also noted by others here on the page on G5 Tower Random Shutdowns.-Mike) was told that a new Logic board, power supply, cooling unit, and processors needed to be ordered. (sounds like there was a leak if all those components needed replacing) The store quoted me a turnaround time a 7-10 business days to allow shipping time for the parts and to test the system. A month went by and I hadn't heard from the store (Thank GOD for my MacBook Pro), so I contacted AppleCare to get a status check on my repairs and was told that the part that they were waiting on needed to shipped from Washington and was being overnighted to the store that afternoon. The store contacted me the next day and left a voicemail on my phone requesting that I call them back. Long story short, they replaced my G5 Quad with a brand spanking new (Mac Pro) 3.2GHz Octo 8800 GT. :-) that put a HUGE smile on my face, needless to say!
Yeeehaw for Apple. Now I know why I have been and always will be a Loyal, Apple Fan!
-Adam"

I'm impressed that they've replaced some out-of-warranty systems like this (and giving higher optioned Mac Pros than base for those that had higher end G5 towers apparently), although some didn't get a no-cost system swap, more than a few have especially over the last 6 months. (One recent report noted he had to pay the est. repair costs to get the new system, but some were offered new systems at no cost.) In some cases in the past, not giving up on the first response (pressing for a replacement/repair at no cost) resulted in getting a new system replacement.

" Much like some of your other readers, I've been having quite a few issues with the X1900 in my Mac Pro over the last few months. I first started noticing it on the PC side, where I'm running XP for gaming. During some Call of Duty 4 Multiplayer games, I noticed some weird things with certain textures (where one texture would "break away" from the surface it was supposed to be on, and then repeat itself all the way to the horizon line in the distance). I hadn't overclocked the card, so no adjustment was needed there, but I figured it couldn't hurt to turn my settings a little lower. That didn't help anything, and over time, the problem got worse, and I would overheat and crash.
My first step was to take a can of compressed air and clean out the inside of my machine, which didn't make any difference, so after reading the article about dust build up (clogging heatsink fins) on the x1900, I disassembled the card and gave it a thorough cleaning. Once again, no luck. It was about this time that I noticed problems on the mac side, where I'd get a lot of artifacts which at first I attributed to working in photoshop for extended periods of time, but it wasn't limited to that. I would end up getting artifacts while just running the finder and mail.app or itunes, similar to some of your other readers' experiences. I started using SMCfancontrl (OS X) and ATItool (Windows) to regulate the fan speed of the card, which seemed to work quite well, though I would still get artifacts after spending time in Illustrator and Photoshop (considerably less than I had experienced previously, but they were still there).

I was clinging to the hope that the 8800s would be compatible with non-PCIe2 systems, but it looks unlikely. (current Mac 8800GT requires PCIe 2.0 Mac Pro) I've also been planning on adding a second monitor, so I decided to try and salvage what I could I from the X1900 by adding the Thermaltake TMG-AT1 (Which does not appear to be widely available -- Amazon was the only major seller I was able to find with the TMG-AT1 still in stock, and they claimed to only have 3 remaining when I ordered mine). (ref: ATI exhausts air outside the case - ref Nov. 30th, 2007 article here on ATI X1900 XT w/Thermaltake TMG-AT1 Cooler Swap) After adding an extension molex cable, I was quickly and easily able to install the new heatsink and fan combo.
I've been using it for about a week now, and have added a second monitor, and things are looking good. My idle temp is about 32°C Mac, 40°C in XP. While I was only able to test it out on CoD4 for about 30 minutes, things seem good on that front (the artifacting would show up within 5 minutes of starting a game, previously) and my temp never went about 66°C. On the Mac side, I've been doing a lot of heavy duty work in Photoshop, Illustrator, and Aperture simultaneously, and there aren't any problems there, either. Only time will tell if it's a long term solution but for the time being, I'm quite happy with the TMG-AT1 (somewhat less happy with the x1900 and Apple).

If anything changes, I'll be sure to let you know.
My config is the dual 2.6, 6GB RAM, 4 HD plus external Firewire HD, running 10.5.2 and Windows XP via Boot Camp.
Thanks for collecting everyone's feedback; Without it, I'm not sure what I would have done.
-Marc "

Here's links to previous posts/articles from Mac X1900 XT owners (cooler swaps, firmware update feedback, notes/tips, etc.)

• Another frustrated X1900XT owner (overheating/artifacts, etc.) (Apr. 2nd, 2008)
• Feedback on Mac ATI X1900 XT Firmware Update (from Oct. 2007 release)
• ATI X1900 XT Artifacts/Overheating Notes/Tips
• Overheating Due to X1900 Dust Clogged Heatsink Fins
• Arctic Cooling Accelero S1 on ATI X1900 XT
• X1900 XT owner notes on WoW FPS Cap preventing artifacts/freezing
• Mac ATI X1900 XT Accelero X2 Cooler Swap
• ATI X1900 TMG AT2 Cooler Swap
• ATI X1900 XT with Zalman VF-1000 LED Cooler
• ATI X1900 XT w/Thermaltake TMG-AT1 Cooler Swap

I had someone else write today about an X1900 XT failure, although OH/artifacts are the more common issue.

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