Hey everyone and thanks in advance for the help...hope I have this in the right forum. I decided the other day to build myself a new system. Current one I have had for 3 years...a record for me. Anyways. I have a MSI K9 SLI-F V2 mobo with a Athlon Phenom 9550 CPU, 2GB of OCZ DDR2 PC2 6400 SLI-ready memory, a WD 80GB SATA drive, a EFX 8800GS PCI-E 2.0 video card and a Ultra LSP 650W PSU. I assembled it yesterday afternoon, everything went together like my previous past builds. Plugged it in and hooked up my monitor, powered it up and all the fans' spun up, the CD drive chirped, the keyboard lights blinked and that was it...fans spinning and humming and no post information on the monitor screen. Checked the connections, still nothing, removed everything from the case and setup with just video and memory, still no POST. Changed video cards, thinking it was a bad card or the system wasn't recognizing the video card due to it being a PCI-E 2.0 card, nada. Originally I had a 400W PSU, replaced it with the 650W PSU, still nada. Checked MSI's site, verified the CPU was supported, did all the trouble shooting they recommended, still no POST. Before I go back to CompUSA and swap try to get them to swap the memory/mobo or cpu, is there anything else I can check? Thanks in advance for your help and or input.