HP’s website has an offer going right now where you can score a free Nook Simple Touch (a $99 value) with the purchase of a new computer. But depending on which computer you buy, you could end up spending several times the cost of the e-reader.

The folks at Dealzon looked at all the computers sold by HP and compared how much you would spend on each if you bought only the computer (using the best available coupon code) and what you’d spend to get the PC/Nook combo (using the best available coupon code that would also work with the free Nook offer).

In many cases, you would pay the exact same price, and there are some instances where the net cost difference is around $30 or $50, meaning you would still be getting a discount on the full retail price of the Nook.

But we also counted 14 computers where the PC/Nook combo would cost you at least $100 more than just buying the PC. In three of those instances, you’d be paying more than $200 above the price of the computer alone, with the worst deal being the Envy Phoenix desktop model h9-1340t, where taking advantage of the Nook freebie will actually cost you $355 over the cost of the computer alone.

Before you end up paying more than you should for this offer, check out the entire spreadsheet at Dealzon.com.

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