Hello, 
I just installed a amd radeon HD 7770 and new 550 watt antec power supply. Now my computer will not boot up unless i put it into safe mode. In safe mode it works normally but outside of that the computer pauses at "Welcome" 

My computer is a GT5449E, the only modificiatinons ive made is add all the memory i could and the modifications mentioned above. The computer was working fine before these instillations. I am currently running on windows 7. 

I have tried installing graphics drivers, but i can not do that in safe mode as it tells me the installation fails due to detection problems. 

When we installed the new products there was no power connected to the machine (all external wires disconnected). plugged in the graphics card with the 6 pin plug. Installed the graphics card in to the correct slot, and made sure everything was in order. We also vacummed out most of the dust before we installed it. 

I will admit i am not the most "tech savy" person but i was hoping that someone may know why my computer can only boot up in safe mode. 

Thank you. 

What did you have before the 7770?

CPU: AMD Phenom II X4 810 @ 3250MHz | RAM: Kingmax 2x2GB DDR2 800 @ 833MHz| MoBo: MSI K9A2 CF v1.0 (BIOS: 1.D)| GPU: Asus HD 6850 1024MB (DirectCu) @ 850/1100MHz | Display: Chili Green Vision L24FHD | PSU: PC Power & Cooling Silencer 750 Quad | OS: MS Windows 95 x64 Edition

CPU: Pentium 4 Northwood S478 @ 3200MHz | RAM: 1,5GB DDR 400| MoBo: Gigabyte GA-8S661FXMP-RZ | GPU: Abit Geforce Ti 4200 | Display: Dimarson 19" CRT | PSU: Noname 400W | OS: MS Windows XP Pro, Fedora 18

He did say GT5449E which is.. http://support.gateway.com/s/PC/R/1009502/1009502sp2.shtml ..which didn't have anything before, intel gma.