Hi, just today I have removed my old Sapphire Radeon HD 7770 and replaced it with an R9 270X VaporX 2gig DDR5 Edition. I also, secondarily, removed my 4gigs of ram and placed in 8 gigs. Everything is secure and set up, but I recieve no signal upon booting up my PC. No errors at all, just no signal. I tried Both the classic VGA cord and the HDMI cord. Neither prevail. Please help.