Motherboards and memory can in some cases be a very tricky combination and some boards are known to be particularly finiky with different types of memory.  Can you look up the memory timings, voltage, etc for your chips, look up what the BIOS is set to use, and post that all here?  The fact that you were able to boot up at all says that the board probably should support the memory, but that doesn't necessarily mean the speed settings encoded on the DIMM are correct (all but one of mine since the 32-bit Athlon XP days have been set incorrectly, when comparing against the manufacturer provided settings). Also, if I'm remembering correctly, #8 was an extremely long test, correct?  If your DIMMs have cooling problems, it might just take that long to start showing the problem.  Can you do something like warm it up inside, move it someplace with a cold air intake (ex. in a garage during the day right now), and run it with the case off?  Do these chips have heat spreaders attached?  As long as you keep it warm, and don't shock it with freezing temperatures right off the bat, the cold won't harm your hardware at all -- just leave it off for a few hours after moving it indoors). Also, have you tested your power supply with a real tester (ie. not just "it boots" and runs)?  Low voltage on the mainboard could be resulting in low voltages internal to your mobo, which can make things start to get flaky, etc.  You'd be surprised how often a PS is out of spec on a typical machine, and it shows up in the strangest ways.  Got a little ATX tester (<a href="http://www.ultraproducts.com/product_details.php?cPath=53&pPath=242&productID=24">http://www.ultraproducts.com/product_details.php?cPath=53&pPath=242&productID=24</a>)? You're welcome to bring the PS in to the meeting on Thursday and use my tester (might not attend, so let me know if you are coming!), or I'll sell it outright for $5 (I want a more expensive one that supports the features on the newer SLI supplies).  The one I linked will work for any 20-pin ATX, and I think it should also do the same set of tests on a 24-pin model since those are backwards compatible with 20-pin motherboards (up to you to check).  Everyone that ever deals with mid-to low range hardware needs easy access to something like this, and I'd still recommend it even if your machines all use higher end supplies (I strongly recommend the Antec Earthwatts series!!!). <div class="gmail_quote">On Thu, Oct 23, 2008 at 9:17 PM, Michael George <<a href="mailto:george@idealso.com">george@idealso.com</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> I have a question for you hardware-diddlers out there.  I bought 1GB of PC133 SDRAM for a Mac.  I got Crucial and it was highly rated (by a whopping 4 people) on <a href="http://newegg.com" target="_blank">newegg.com</a>. I put it into an ASUS A7V system to test it.  I have a 256MB PC133 DIMM that works fine and tests fine with Memtest86+.  However, when I put either of the 512MB DIMMs into the system and run the test, it will fail on test #8.  It seems a rather odd coincidence for both of them to fail the same test, but the 256 passes just fine. I'm running Memtest86 on one of the DIMMs in a different slot on the mobo to see if that might have something to do with it, but it seems unlikely as the 256 tested just fine. Is there perhaps some idiosyncrasy of which I may not be aware that could be causing this?  I don't want to RMA this RAM only to find that the test was flawed, not the memory... Thanks! -- -M There are 10 kinds of people in this world:        Those who can count in binary and those who cannot. _______________________________________________ linux-user mailing list <a href="mailto:linux-user@egr.msu.edu">linux-user@egr.msu.edu</a> <a href="http://mailman.egr.msu.edu/mailman/listinfo/linux-user" target="_blank">http://mailman.egr.msu.edu/mailman/listinfo/linux-user</a> </blockquote></div>