Mauro Maroni <[EMAIL PROTECTED]> posted [EMAIL PROTECTED], excerpted below, on Wed, 08 Nov 2006 20:25:25 -0300:
> Well, then I got segfaults compiling other packages, and a couple of > times the machine freezed doing trivial things like browsing the web. > Could this be a hardware issue? RAM seems to be OK as I ran memtest > during the night and did not show any error after 9 hours. That's a classic hardware issue, yes. The cause can be one of several things. Note that there are at least two ways RAM can be bad and memtest checks only one -- memory actually corrupting in storage. From hard experience, I know the other one all too well -- AND know that memtest doesn't catch it AT ALL. That one is memory timing issues, and as memory speeds increase, it's becoming more and more common. Taking my case as an example, the RAM was rated PC3200, but simply wasn't stable at that. Unfortunately, my mobo was new enough at the time, and using the then new AMD64 memory-controller-on-CPU technology, that the BIOS didn't have the usual memory speed tweaking options. After fighting with it for some time, a BIOS upgrade was eventually made available that added these options, and a very simple (with the right BIOS option) tweak to reduce memory clocking from the rated PC3200 (200 MHz DDRed to 400, times 8 bit bus width, equals 3200) to ~PC3000 (183 MHz DDred to 366, times 8, rounds to 3000) eliminated the issue entirely. The system was then rock-stable, even after tweaking some of the detailed individual wait-state settings back up to increase the performance a bit from the defaults. So, before you eliminate memory as a possibility, check your BIOS and try declocking it a notch or two. Actually, all the hardware possibilities trace to the same root, what should be a binary one becoming at times a binary zero, very often due to undervolting. This can be due to speed issues, as with the above or if you overclock your memory or CPU, or power issues, which may occur anywhere in your "power train", from the stuff coming to you from your electricity supplier, to an underpowered computer power supply, to an underpowered single voltage rail on that supply, to an underpowered UPS, to a faulty power regulator on your mobo, to a bad connection somewhere, to simply having to many things connected to the computer at once. Or it can be both power and speed issues, since higher speeds commonly require more power in ordered to remain stable. (This makes perfect sense given that higher speeds mean there's less time to actually bring the transistor to the high voltage "1" state before actually seeing if it is a 1 or a 0, and boosting the supply voltage -- to a point -- can often make it reach that state faster.) So, it should go without saying, but cut the overclocking if you were doing it (and note that overclocking can cause permanent damage even after returning to normal clocking) Next, check your power supply, both at the wall plug and that you are using a good PSU in the computer, sufficiently highly rated and UL Listed (if in the US, substitute the appropriate authority if elsewhere), since it's common knowledge that the rating of many power supplies lacking this listing aren't worth the cost of ink used to print the rating. If you are using a UPS, check that too. Finally, check for overheating. Those are the most common hardware causes of instability. -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman -- gentoo-amd64@gentoo.org mailing list
