Hi, the other day i bought 512mb DDR RAM (as 2x 256mb sticks) and this morning they came in the post. I took the old SD RAM out and put the new ones in my pc and when i turned it on, the hard drives and cd drive span up and i thought it was going ok, but i turned my monitor on to find that it said No Signal. I tried a couple more times just to be sure, but the same again. I just checked the mobo manual and it says that what i have should be compatible and i even opened the case and wiggled a the video card etc to make sure that nothing was loose but now i've put my old ram back in and it's ok. Does anybody know why it wouldn't work with my new ram or do i have to change the BIOS or something because it's a different type to the old ones? Any help would be appreciated. Thanks.