I'm getting a peculiar problem cropping up now and again. After a random period of play, I keep getting what I can only describe as 'columns' appearing on the screen, as if a wall had suddenly appeared at ground level, stretching into the heavens. I also get strange extensions on people's arms (eg workers suddenly having their left arms extend into spikes). Basically, it looks as if part of the image has been 'sucked' upwards or outwards.

I'm not explaining this terribly well, so I'll post a screenshot when I can.

I can only assume it's a graphics card issue, as I'm also getting the same problem when playing The Movies. Only more often, and with a screen flicker of the kind that causes seizures... :twitch:

For everyone's info, my system specs are as follows:

3GHz Dual Core Mac Pro, 4GB RAM, OS 10.4.11, 512MB ATI Radeon X1900 XT

Anyone got any ideas? Thanks in advance.

There have been past reports of problems with the early Radeon X1900 XT. I know a lot of people on various forums have reported getting the cards replaced in the past. Maybe you are the latest victim?

Read the Apple Store reviews ( http://store.apple.com/us/product/MA631Z/B?fnode=home/shop_mac/mac_accessories/displays&mco=MTA4MzA3 ), or run a Google search on "Mac Radeon X1900 XT problems" for other examples.

There are some people on MacRumors (http://forums.macrumors.com/showthread.php?t=482534) who recommend cleaning the card, as these graphics problems can be related to over-heating.

I had exactly the same problem. Your X1900 XT is fried. Apple knows about this and will ship you a free replacement (I hope you have AppleCare). Apple refers to this as the WoW problem because it first showed up in large numbers when World of Warcraft came out for the Mac. The original manufacturer of the X1900 XT cards produced a defective card and the new card Apple is shipping was made by another company. My new card works perfectly.

Oh dear. I do have AppleCare, yes - now I'm going to have to dig out all the paperwork.

(Thanks very much for the info, anyway.)

For anyone else interested, I've found an entire thread (http://forums.worldofwarcraft.com/thread.html?topicId=94000596&sid=1&pageNo=1) about this issue at the WoW forums.

Removed the X1900 this morning - heat sink clogged with dust (at first, I thought it was some kind of fabric draught excluder, until I looked more closely...). Anyway, I've cleaned it out so let's see if that makes any difference at all. According to some reports it won't help in the long run.

While I had the card out I checked the serial number and it's a revision 1 (number ending in a 4), not the apparently more reliable revision 2 (number ending in a 6). So I'll probably have to get a replacement at some point. (Image here (http://jeffgiacomi.com/ATI1900XT/Back.jpg) [via WoW forum], for anyone else digging out his/her card and wanting to know where the relevant serial number is.)

Let us know how it works out.

Just been playing The Movies with no problems, but I don't want to push my luck. See how it goes, but I imagine I'll be ringing Apple at some point.

(For the record, I also updated the firmware and installed smcFanControl just to cover myself.)

Two months on and the problems have largely gone away, although I'm noticing some graphics tearing - but I probably need to give the card another clean.

Alan - any idea when the new AMD 3870 might be available in the UK? [EDIT: Scrub that, I found it already.] I imagine it will only work with Leopard, however, and I'm still running Tiger. I like the look of the review of the 3870 (http://www.xlr8yourmac.com/Graphics/ATI_3870_Mac_PC_review/radeonhd3870_review.html#storytop), mind.

Have you contacted Apple about a replacement yet? I would certainly recommend doing so unless you plan to upgrade the card soon.

Just updating this thread. I didn't bother with a replacement 1900, they've had too much bad press. Instead I bought the new HD3870 - installed it yesterday (having upgraded finally to Leopard in the meantime) and, fingers crossed, no problems so far. Will let you all know if the graphics glitches continue, but I really ought to be safe now.

Thanks to everyone who helped.

[UPDATE: Almost a month on, and no problems whatsoever. :goodjob:]