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I won't go into specific reasons you mention, but it is perfectly possible to write code that has a known, fully deterministic result. After all: compilers produce machine code, and the bulk of that is integer operations which have exactly defined behavior with 0 room for interpretation (when it comes to digital logic like CPU's, "defined" is deterministic). Maybe there are exceptions (like floating point? don't count on it), maybe for some types of operations you need to sidestep a compiler and code some assembly directly, but that's beside the point.

With that in hand, expect some of computed results to turn out wrong. Knowing what junk parts go into computers sometimes, how shoddy some machines are built, and how some people abuse their computers, I'd think a 1% failure rate is probably on the low end of the scale.

For example, try running Memtest86 sometime, leave running for a few hours, repeat for other computers you encounter, and see how many computers you need to try before you see it spit out errors. You might be surprised.

The tools to make a bootable USB-stick aren't quite there (or weren't there 4 months ago at least). On any OS (not win XP) there is a built-in way to burn an ISO. There is no corresponding way to do it for an USB stick. Even if you can use dd on Unix-like OSes, the ISO is still the king of the bootable images. See for example http://www.memtest.org/#downiso. What would you get if you wanted to boot from an USB-stick, and was using a FreeBSD desktop? I didn't try the "pre-compiled binary", since I knew the ISO would work...

In the volunteer aspect it is more of a passion based decision than an recruitment oriented process. My advice is find something you both care about and also feel the site in question needs improvement. Next, simply hop on the forums or news feed and offer your services. It doesn't necessarily hurt to have some material already developed to get the discussion flowing.

Higher profile is probably going to be a bit more difficult so you may not want to go looking for the top 10 applications of all time. Those circles (even of volunteers) tend to be more work to edge your way into responsibility. Still, my experience has been very positive with contributions and generally working with a project I do not own. I had a good deal of fun one weekend with a BitPim developer banging out support for my phone.

If you need explicit areas where your talents could probably be used I highly recommend seeing if you can get the guys over at http://www.memtest.org/ to let you revamp their page. The program is nice, but the web page is atrocious.

Does anyone else have any suggestions for who needs a make over? (That could be a reality series television show!)

"...but, in the end, the computer still is that magical logical machine. That's my view -- is it yours?"

No. At some point any sufficiently complex piece of deterministic logic becomes indistinguishable from randomness, and PCs are past that point for me. The beauty of the underlying logical machine is totally obscured by the apparent randomness of errors that go away after rebooting (or sometimes just issuing the same command again).

Some days my map prints perfectly, some days it comes out with extraneous pink lines all over Florida, some days it crashes the plotter so badly it needs a hard reset. Logically, I know the problem isn't "luck" or satanic printer gremlins, and that it must be some subtle, deterministic interaction between the source data, the GIS software, Windows, HP's print driver, and their plotter firmware, but damned if I have the time or the skill or the source code to track it down. It's easier to just mumble obscenities about wasting ink and paper and try again (faster, and more likely to result in a correct print, too).

If the problem is random, you probably have bad memory, either in your PC or in your printer. With consumer grade equipment, it's more common than people think.

Download the bootable ISO image from http://www.memtest.org/ and run it. If it finds any errors at all, replace your memory until it doesn't. Unfortunately, the printer is harder to check.

If it really is a software bug, you should try different printer drivers. Most HP models can use either a PCL or a PostScript driver, and they're quite different internally, but print essentially identically, so can be used interchangeably. If there's some random bug in one, it's unlikely to also be in the other. Similarly, many models have both PCL5 and PCL6, try both.

Granted, it does directly or indirectly stress the fpu, cache, maybe task switching and interrupt handling. However, there are many more things that can go wrong.

Off the top of my head, I can think of a lot of things that specifically need tested that one program probably won't do. For example, you need to verify both 32-bit and 64-bit operations. Prime95 is specifically compiled for one or the other, so would stress less of the "other" version.

There are also a lot of SIMD instructions that need tested. Some are obscure enough that only a few apps would use them.

Then, there's all the instructions that support virtualization. I have found that bad hardware running a hypervisor will fail much more frequently than if it is running a "normal" OS (YMMV).

But, unlike Memtest86+ for RAM, there doesn't appear to be any program that specifically tests all CPU subsystems (registers, cache, instruction execution, etc.).

The randomness of failures suggests that Firefox writes to a random location memory that is important in some systems and not others. That's crucial in an unstable, poorly designed OS like Windows XP. Linux merely throws Firefox off the system.

What that suggests to me is that your memory is bad. Try running memtest and see if it reports any errors. Even if it doesn't, it might be heat related.

I've had issues with Firefox crashing in the past (although mostly due to my playing around with XPCOM while writing an extension), but I've never seen it crash the OS. If it's crashing the OS, it seems highly likely to me that there's something physically wrong with your system.

After all, even Linux crashes when the CPU physically falls out of its socket. (Don't try that at home.)

The last time I was routinely crashing Windows XP was due to an overheating issue with my graphics card. It'd run fine until I tried to play a game. Start up a game and then after a while, boom: PAGE_FAULT_IN_NONPAGED_AREA.

Then install the memory and run memtest again. If it finds memory errors, you may very well be looking at a bad stick of ram. If it doesn't, you may be looking at subtle timing issues in your ram; I've found had machines that can pass a 7 day burn in running memory tests without error and can't get Windows booted up with a certain memory stick installed. I don't know if that says something about memory tests (I've used several), memory itself, motherboards, or Windows, but it is the nature of the beast. It can be as complex as timings that don't quite work with the motherboard or a power supply whose voltage drops a few tenths of a volt when the load from the graphics card comes up. It's one of the reasons I spend the extra 20% on 'name brand' (kingston, crucial, etc.. I'm not picky, just not buying generic green stuff), memory errors can be very subtle.

As to why things ran fine? a couple of possibilities:

• Infant Mortality: Mass produced items (such as memory, pwoer supplies, hard drives) generally fail quickly or last a long time. It could be
• Marginal building corruption: Files have been messed up. the registry is a little borked. The system SEEMS fine but in reality has become a little corrupted from the bad ram. With the additional errors caused by the ram, pci.sys wouldn't load. Now it works, but you may run into other problems down the road

And what I'd probably say when you called:
If you've added ram in the last month, then it's very likely that, remove the ram and see if it boots. Even if it appears to work, there could be subtle problems that crop up. Try it and see. If removing the ram doesn't work, it could be:
a: Motherboard
b: Hard Drive
c: Still the ram
d: The hard drive connector cable (I have 80% of a sata cable on my wall, the cable of doom. 3 computers would boot and run with that cable on it's hard drive, but will bluescreen or segfault within 2-3 hours of power on, unless all the hard drives were hitachi. the reason it's 80% is I cut the end off after it got put into the third machine, even with a 'funky do not use' label attached. Why do I keep it? First time I threw it away someone dug it out of the trash and used it. I dunno about people, honestly).
e: Windows PMSing
f: Power Supply... yes if it's almost but not quite powerful enough it'll make a machine go wonky, really.
g: Power strip. You laugh. I've had at least a dozen machines that were fine when taken off the dollar store power strips some people use.
h: The computer gods are laughing not with you, but at you: Seriously. I had a Dell that wouldn't work at the secretary's desk. It worked elsewhere in the office, plugged into the same keyboard/mouse/printer/monitor, even ran an extention cord back to keep it plugged in the same power strip. We finally swapped hard drives with another same model Dell, moving the rest of the machine across the room, and both machines were solid as a rock.

There are two of them:

http://www.memtest86.com/
http://www.memtest.org/

Or use both?

6.1a won't even install on my Inspiron 9400, giving me a "memory parity error" on the initial reboot test for full drive encryption.

Have you run memtest86+ and let it go for at least two full tests? Could be one of your sticks is bad.

The POST a typical non-server grade system does some very weak memory tests. In all the cases I've seen of bad RAM in the past few years the POST never said anything. Skipping the memory check would be no big loss.

If you suspect your memory really is bad, run a proper memory checker. They catch far more memory faults than the POST does,

There is plenty of free open-source software on OS X if that's what you're looking for, it isn't magically turned into shareware

Actually, it is. Take Memtest86+, the de facto standard RAM tester. Now Google for "memtest os x" and you'll find this jerk who sells a compiled version but doesn't make the source available to it. To rub salt in the wound, he's too lazy to make his own website graphics and uses the default "Joomla! ...because open source matters".

Sure, you can get Memtest for free if you know how. It's just irksome that the source-deprived shareware version is the one most Mac users will know about. So one program isn't the end of the world, but it seems par for the course for OS X.

My experience is that Linux tends to tolerate faulty hardware better than Windows. I run http://www.memtest.org/ on a machine for 24 hours. If there are no errors, then it will run WinXP and will be extremely stable. If there are minor non-repeatable errors then I know that I can safely run Linux on it, but not Windows.

Make Memtest a grub boot option and use it before you travel or put your computer someplace others can get it. Security like that is a bore. I'm going to enjoy better sleep/wake.

A fun question is if cheap ram can help save M$. If the 4GB Vista "sweet spot" is any guide, Windows 7 will require 16 GB. Cheaper faster memory might actually get there but processor and network speed is likely to catch up to Vista at the same time God makes a rock so heavy he can't lift it.

http://www.memtest.org/#downiso Bootable from USB Drive, CD, or Floppy... ...A standard troubleshooting tool in my TS kit. Sure, it takes some time, but it eliminates instability/random software/OS issues and verifies the RAM is 100% IN SITU.

I was thinking the same thing. He should check out http://www.memtest.org/.

is the memory tester...

That's not an reason. Just pull off a freeware tester. I've used http://www.memtest.org/ using the bootable CD
version on a few occassions and had it pick up problems on two seperate occassions.

I've run firefox on 3.0 (and now 4_BETA) pretty much every day, and the last crash I had would have been a couple of months back (I had a dozen or so MB of XML files open and multiple media playing windows).

One thing to definitely test would be your machine's memory. If you can write a CD or floppy image I would strongly suggest downloading memtest from http://www.memtest.org/ and leaving it running overnight.

Try to install Ubuntu without random crashes all the way, including some Python entrails thrown into your face.

Perhaps you should consider running memtest86+.

Have you checked your RAM? Bad RAM could easily cause massive instability in both OSes. There's no reason why either Linux or Windows should crash so quickly. Try Memtest86 or its successor/fork Memtest86+. A quick test is to copy a large file and then md5sum both versions. If the MD5s are different, you may have bad RAM.

Also consider Memtest86+. Supposedly, it is kept more up to date. I know that Corsair Memory recommends it over Memtest86.

Although Memtest86 is absolutely great for detecting memory errors, I perfer Memtest86+.

It's a more updated version of Memtest86 (which was last updated in November!), from the x86-secret team. It'll do the same thing, just that it will identify all the new procs and chipsets better.

http://www.memtest.org/

PS: I find if the RAM has any errors, the Modulo-20 test will nail them. Methinks it's test number 11 in Memtest86+.

Solution:

1. Compile a Linux kernel with the BadRAM patch.
2. Run Memtest86+ to get a list of bad areas.
3. Profit!... erm, I mean a Linux system with lots of cheap ram!

If the BSOD errors are totally random have nothing in common with each other, it's almost always a RAM issue. If you want to be sure it's a memory issue of some sort, check out Memtest86+. If it detects errors, then you need not go further with the troubleshooting untill you fix this problem first and foremost.

http://www.memtest.org/

I tend to have better luck with memtest86+, especially on newer/odder systems. It was originally (still?) from the same codebase.

Actually these days you'll want to use memtest86+ since it's current and is regularly updated

The best tools for checking memory are memtest86 and the follow-up memtest86+.

Both of these are free to download and use. I usually leave them running for roughly 24hrs for a reasonable level of confidence. You should also burn-in the other major components too but memory is the best place to start.