The CyberPowerPC has the best CPU and GPU but a really poor power supply (replace at first opportunity).
The HP has the worst video card.
As for running GW2. PvE, non zone events should be fine with the CyberPowerPC model, world boss and WvW, well manage your expectations.
This CyberPowerPC model has a bit better PSU than your selection.
http://www.newegg.com/Product/Product.aspx?Item=N82E16883229486
One “problem” with both CyberPowerPC models is I suspect the HD 7750, being a 2GB model, is using DDR3 memory which essentially knee caps the GPU.
Now for a few dollars more …
http://www.newegg.com/Product/Product.aspx?Item=N82E16883227491
Being an HD 7770 1GB model I suspect it’s GDDR5 memory.
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