I will try to explain this to the best of my ability. I am new here so any suggestions regarding posting would be appreciated. Here goes: I have built many pc's in the past with success...however, I am doubting myself greatly at this point. In fully upgrading a older pc for a friend, I installed a new mobo, KM3M-V. It powers up perfectly no beep errors, however, no video signal at all. I tried on 2 working monitors. My son's pc, also needed to be hooked up so he can have it when school starts (unhooked due to a recent move). Anyway, his board is a MSI K7N2-L To my horror...I got the same result. My board that I am using now is a Nforce4M-A and works perfectly with both test monitors. I realize all of these boards are different and here is what I have tried so far: I have changed out PSU's on both non vid signal boards (with older untis and less power) and both power up with no problems. I do have the 4 pin cpu power hooked up on both boards (however, on the KMM-V, I had to use an adapter to do so) I have used 3 or 4 different video cards in both non vid pc's and that failed as well. I cannot get to a BIOS screen. there is no signal at all. I have swapped DIMM sticks and made sure everything is connected. My prcessors are also working on both boards. I have cleared the jumpers as well. Both boards hae onboard vid and I have tried using those as well as various (at least 4) video cards. I have been swapping and changing parts for 3 days now and I am desperate to get this resolved. It is fun for a while, but now I find myself on the verge of a fit or simply in tears...lol...If anyone has any ideas at all, please let me know...I would be most grateful and so would everyone in my household who has listened to me whine for 3 days....and the PC Carcuses (at least 7 of them) are not looking very well laying all over the house. Thanks in advance.