well i picked you out a quad core because it fit in the budget with a few bucks still left over.
the 550 is a good cpu too, but if you want, go in between the quad and dual and get this 720 triple core, which is only $20 more than the 550.
i was asking for some psu info because you dont want to get some new parts just to find later that your psu crapped out on you and fried your parts.
these parts are $361, so if you're not sure about your psu, you have some room to sqeeze in a better one, like an antec psu.
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still the same mobo (they lowered the price by $10 O.o) and gfx card, except you get the 720 tri-core, and this ram is a great deal at that price.
edit: i really don't know whether there will be a problem fitting a new mobo into the alienware case. i know that big companies like dell and hp usually make it so that their cases only fit their mobo's, but i don't know about alienware. because you have to make sure that the mobo's mounting holes line up to the ones in the case.
acutally, i think alienware is owned by dell, so that might also be the case for them. someone else might know.
if it turns out that it will not work, this is a great case for tight budgets.
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