I have two Optiplex 755's that I have upgraded with 8gb RAM, faster processors (from suggestions on this site) and SSD drives. I have Win 7 64 bit on one and win 10 64 bit on the other. They both have BIOS revision 22A and the latest chipset drivers that I can find here. They both seem to be running just fine, with no bangs in Device manager. I wanted to upgrade the video card to one that would support 4K resolution on my new Samsung TV. I found what I think is the lowest power card made that will do this, the XFX card using the Radon RX460 graphics processor. I installed it and got a code 43. I can not find the specifications for the 755 mini tower power supply. This card needs 400 watts.
if, as I suspect, the PS is too wimpy, and cannot be changed out because it is proprietary, does anyone know of a graphics card that will work and still support 4K resolutions?
Be careful - many of the newest generation of Radeon and GeForce cards require a system with a UEFI firmware your system does not have.
The power supply in the 755 minitower will not be anywhere near 400W -- but the lack of UEFI will render the power requirements a moot point.
My research is indicating that an HDMI 2.0, instead of the more common HDMI 1.4, is required to pass the required resolution. Does anyone know of a lower power card that utilizes an HDMI 2.0? That specification is not always easy to find in the Spec sheet when looking at new cards.
The EUFI caution is worth noting, however, the technician with XFX was aware that I had a BIOS because he asked me which version I had.
AMD R series cards DO NOT and WILL NOT work due to UEFI BIOS issues and Not supporting DOS VESA Video mode 103. This has nothing to do with power and everything to do with PCI-E version and UEFI vs CSM Legacy option rom support which is non existent in The RX460. Geforce 610 630, 710 720 730 740 etc work fine as long as they are not longer than 8 inches and use a single not a DUAL slot.
LOW Profile 25W or less cards are required for Desktop and SFF systems. USFF has no card support because it has no slots.