Niether they are both as bad as eachother, Alienware's are just overpriced for what they are and the second pc the old cpu and gpu for the price off the pc you could build your own for probably less then what that pc actually costs so i'd recommend building your own.

neither is better as they are both terrible.

What is your budget and currency? (Pound sign does not work normally, use GBP abbreviation)
Do you need a monitor?
Do you need a keyboard?
Do you need a mouse?
Do you need an operating system?
What will you use the PC for?

When you buy Alienware or most pre-built, you're buying the lights and case. Never worth or even near the amount they sell for.

What is your budget and currency? 500 or 600 dollars.
Do you need a monitor? I have a monitor but its kind of bad.
Do you need a keyboard I have a keyboard but its kinda bad.
Do you need a mouse I have a mouse buts its kinda but
Do you need an operating system yes
What will you use the PC for? Playing games like Garrys mod. GTA V. Call of duty. Battlefield. Minecraft sometimes. Making and uploading videos to youtube.

You can get an OS for free and the peripherals will do.
Unfortunately, i'm a tad over budget BUT, it will be worth it.
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