New guy on this forum. I have seen some threads that I thought related to my problem, but they did not go there. I have been repairing and upgrading computers for friends, family and my employer (a small non-profit) for several years. Now, for some fool reason, I decided to try to build myself a new system. I have a Dell P-III @ 1.0GHZ that works just fine, but some fools have to test their luck. At any rate, I did my homework, I think, and ended up purchasing an Intel Mobo (D865PERL) and the boxed P4 processor @ 3.0GHz w/800MHz FSB. Although it is a dual channel configuration, I purchased only one (run in single channel mode) PNY Optima PC3200 DDR400 512MB. For the case I purchased an Antec Sonata w/380W ATX 12V power supply installed. (beautiful case - super quiet). I VERY CAREFULLY, following instructions/manuals, assembled the components and installed WIN XP Home. And it worked. For a few hours. I did a reboot after installing (nothing fancy) Adobe Reader, and it locked up as it was running the POST. That is as far as it will go anymore. I have totally disassembled this thing (with the exception of the CPU and heatsink fan - since I don't have any "thermal stuff" available) and reassembled with no change. The system powers up, it sees the video card , checks the memory and acknowledges the presence of the keyboard and mouse. Then, nothing. I can get into the system setup during this much of the POST/boot, but it never even gets to the FDD so I can't do anything additional. I am waiting for an e-mail response from Intel and Antec, grasping for some guidance. Any thoughts anyone out here has would be greatly appreciated. (I'd hate to tell my wife I have $600 worth of scrap down in the basement ) Thanks for any assistance.