My brother bought some ram about a week ago and when he got it home he found out it won't work in his computer case the speeds were different. So of course he tossed it my way. So I installed I tried to boot up and see if it works but nothing showed up on the screen besides the monitor self test to say its working properly. I removed the new ram and put my old ram back in but the problam still remains I try to boot it up and nothing appears on the screen besides the monitor test then after a minute it shuts off. I can't even get it to a safe mode or anything. the mother board is a Pen 4 D915PGN model I am currently useing windows pro. My old ram combined was 512 and I attempted to put 2 512 chips in but even after I switched back to the orignal the problem still remains =/ Could anyone please help me am so lost.