Both of my family's systems have these Mobos w/ Intel Celeron D 346 Prescott 3.06GHz CPUs and MSI NX6600 TD256ESP Video Cards in the same generic model of mini-tower case. One Mobo is about 90 days old [hereafter: OLD], another 30 days old [hereafter: NEW]. OLD is on 4-6 hours per day; NEW is on almost 24/7. I've been running 2 PQI 1GB DIMMs (MAB42GUOXE-X2 plus heat spreaders) in each since I've owned each of them. Each system has worked well. Just today, I realized page 15 of the Mobo's O/M, which says . The O/M doesn't say it can't support higher-voltage DIMMs... and BIOS even has settings to up the DIMM voltage to 1.9V, 2.0V, 2.05V etc. The PQI DIMMs above are 1.9V. Since I wasn't having a problem with the initial DIMMs/Mobo combinations, earlier this week, I bought 2 more of the same DIMMs and added them to NEW. In my next 20-or-so "power on" attempts of NEW with 4GB inside, I only succeeded on try 3... and again on or about try 8. I've since tried powering NEW with just its original 2GB... no success. None of the failed attempts in NEW (w/4GB or w/2GB) have managed to engage the Power Supply fan. I checked all the connections; nothing looks/feels loose. I swapped power supplies (identical models) between systems; NEW still doesn't work... OLD still does. I swapped DIMMS; NEW fails & OLD works. Troubleshooting is ongoing. The bottom line: could filling the Mobo with 4 DIMMs that are 0.1V out of spec (a vague spec at that) fry the Mobo?