Quartus II v6.1 crashes my PC

[Altera_Forum]

Hi there, 

 I have a very annoying problem: Quartus makes my PC crash! I am running Quartus II v6.1 on a single-cpu (but hyperthreading) machine on Windows XP Professional. Everything was fine until today, when suddenly my PC crashed while Quartus was compiling my design. I thought that this was a nonrepeatable accident, but I was wrong: I cannont compile my design without a crash anymore.   I have experienced two types of this crash so far:  1. The PC screen immediately goes black, then the PC reboots. 2. The PC screen freezes (the mouse pointer is stuck) and I can only hard reset it after having waited several minutes and nothing changed.   What I already tried: 1. Reverted the design (the Quartus project directory) back to a known "good" state (I use Subversion).  2. Deleted the database directory "db" 3. Deinstalled Quartus, removed all traces of Altera and Quartus in the Windows registry, and reinstalled Quartus  Nothing helped so far!  I already had this problem a few months ago, at that time I tried the following: 4. Running a RAM Test 5. Running a HDD Test 6. Deleted and re-created all the Quartus project files 7. Tried to open a different, Quartus project known to be working  At that time, the only thing that finally helped was format c: and a complete reinstall of Windows, Quartus, all Apps and stuff. After that, all the projects worked fine again, but I didn't change anything: I simply have left them untouched on a second partition of my HDD and opened them again after the reinstall.   This problem already cost me about a week of valuable development time, and if possible, I don't want to do a complete reinstall to get Quartus working again... especially because the problem seems to reappear after a while.  Does anyone have a similiar problem? Any suggestions?  Please help! MrNewman

[Altera_Forum]

No matter how bad of a coding mistake, Quartus should always crash nicely within the windows environment(internal error, maybe worst case is Quartus "disapearing"). The fact that it brings down your system is worrisome. I've seen this once before(someone locally in the office), and his problem ended up being a RAM issue. (He thought it was Quartus, since that was the only thing that caused the problem, but it was more because Quartus was the only thing that used so much RAM it encountered the bad area.) I know you've already run some tests, but that is the only thing I could think of. And something that was truly just a bad line of code in Quartus should be repeatable, i.e. every time you compile it, even on different machines, you get the same problem. That doesn't seem to be the case here. 

Can you upgrade to the latest version of Quartus? I really don't think that's the problem, but at least it's another data point. Do you work with someone who has another machine and could run some of your compiles for a few days(not as a workaround, but to see if it is machine specific). Just some thoughts, but good luck.