Get Temperature Monitor to see if it's heat related...
And/or iStat Pro...
What are the highest temps?
With your suggestion, i turned off mini and waited it to cool for about a couple hours. Then I turn it on with iStat pro running. After about 15 minutes light load since it booted, it started to show green snow again. The temperature of north bridge is 55c, with everything else lower than that. I don/t think i can rule out temperature completely, but 55c doesn.t seemto high...
Correct, those temps aren't bad for IntelMacs...
One way to test is to Safe Boot from the HD, (holding Shift key down at bootup), run Disk Utility in Applications>Utilities, then highlight your drive, click on Repair Permissions, Test for problem in Safe Mode...
PS. Safe boot may stay on the gray radian for a long time, let it go, it's trying to repair the Hard Drive
Reboot, test again.
If it only does it in Regular Boot, then it could be some hardware problem like Video card, (Quartz is turned off in Safe Mode), or Airport, or 3rd party add-on, Check System Preferences>Accounts>Login Items window to see if it or something relevant is listed.
Check the System Preferences>Other Row, for 3rd party Pref Panes.
Also look in these if they exist, some are invisible...
I am about 90% sure it is faulty mini-DVI port.
- I've booted into the "Safe Mode" make sure no other suspectable process was running
- I've got a new mini-DVI to DVI adapter
In both cases, the screen consistently becoming snowy when the northbridge temperature rose over 55 °C. The screen become completely sonwy after 60 °C.
The mini display port doesn't seem to be affected. However, the quality and color is not as good as with DVI. And now it cannot do dual monitor any more.
The questions now are that
- how much will it cost to fix this thing?
- Is it possible to fix it by myself?
I am a bit disappointed with Apple's manifacturing quality. After about 2 years of light use (no game, just a bit youtube, internet browsing and middle school home work with MS Words), the hardware is breaking down...
Update - I switched my larger LCD monitors (24-inch 1920x1200 DVI) with smaller LCD monitors (17-inch 1680x1050 DVI). Mac mini seems to be able to drive 2 smaller screens without going snowy.
A little bit suck but at least I still have 2 digital output to dual screens. I hope this work around can last me the life time of this mini.
Can you confirm whether you are using an original Apple apple adapter or a knock off?
I have used both original and fake adapters and found the knock-off adapters are much more sensitive as one time I got a snowy screen on my 23" Dell (DVI) using a knock-off adapter. Checking the connection fixed it. Never had this issue with an original Apple adapter.