If disabling any antivirus software, and it`s real time system protection does not work.
I would check your system for any missing motherboard drivers.
As it looks to me that the driver is trying to check something to do with the chip set of the motherboard other than the graphics card in the system.
And why it would halt at analyzing the system.
An easy way to tell is to click on start, control panel. and device manager of windows.
If next to any bit of hardware listed you have a yellow exclamation mark it means you need to install a driver in most cases for your motherboard.
And as said is probably the cause as to why the ATI graphics card installer halts at the analyzing your system.
You should also be aware that some R9 270X cards require extra 12v Pci-e power to be connected from the psu of the system to the card.
If you have failed to connect these the result is also the Ati driver install halts due to a lack of power to the graphics card, as it canot be detected in the system due to it, Jared.
I`m betting that may be the cause so check to see if you have connected power to the graphics card from the psu of your system.
??? Double check Jared.