okay been looking at this pc from a uk retal site called very.co.uk also on littlewoods.co.uk its an acer g3-620 and i contacted them via there web chat and i asked the person what PSU does this have because it as a gtx 770 and all he could find out was he thinks its a 500w PSU surely that can't be right?
the bare minimum should be at least 600w
http://www.nvidia.com/content/geforce-gtx/GTX_770_User_Guide.pdf
specs
Processor- Intel® Core™ i7 4770
Memory- 16Gb
Hard Disk Drive-2TB
Graphics- NVIDIA GTX 7700 2Gb
Operating system - Windows 8
Optical Drive- DVD-RW
link to pc
http://www.very.co.uk/acer-g3-620-intelreg-coretrade-i7-16gb-ram-2tb-hard-drive-desktop-base-unit--with-2gb-dedicated-graphics/1346264984.prd
the bare minimum should be at least 600w
http://www.nvidia.com/content/geforce-gtx/GTX_770_User_Guide.pdf
specs
Processor- Intel® Core™ i7 4770
Memory- 16Gb
Hard Disk Drive-2TB
Graphics- NVIDIA GTX 7700 2Gb
Operating system - Windows 8
Optical Drive- DVD-RW
link to pc
http://www.very.co.uk/acer-g3-620-intelreg-coretrade-i7-16gb-ram-2tb-hard-drive-desktop-base-unit--with-2gb-dedicated-graphics/1346264984.prd