RE: upgrade x51 r2 or rebuild completely?
The NVidia GeForce GTX 960 is the highest NVidia GPU upgrade that we can support for the Alienware X51 R2. We recommend using a 330W PSU with the GTX 960, we do support a 330W PSU for this system. We only support the stock motherboard that came with the system.
Dell | Alienware Technical Support
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