so Microsoft choose
8/16 GB DDR3 30$-60$
eSRAM 30+ $
Move engine blocks don't know how much they cost in R&D and to add in silicon, around 20$?
for a range from 80 to 120+ $
adding to this complex development to internal software tools and to developer's engines and code
trying to catch 100-105 $ of simple 8 GB GDDR5, nothing less, nothing more?
it's no cheaper, where's the sense of it?
nobody has the doubt that maybe the things are different?
Well these figures are just total guesses on your part. The move engine blocks are probably not that big a deal at all, I would figure negligible cost for those not $20 (hell when they were first discovered people were trying to downplay them saying all GCN GPU's already contain something similar, the Durango ones might be just slightly modified/beefed up)
The ESRAM cost MIGHT be a decent guess. But I think the key there is that silicon cost should fall while RAM cost generally wont. So MS might gain a bigger cost edge after some shrinks than initially.
At the end of the day the cost difference between 8GB DDR3 and 8 GB GDDR5 is going to be very significant. It's probably $30 vs $120. And BOM differences tend to be multiplied in retail pricing (partly why you pay $100 more for the hard drive equipped model of Xbox when it probably costs $25 more)
As I've said all along I dont know that you'll necessarily see that difference in pricing though, MS can pocket the difference, there is Kinect 2 pack in costs to consider, etc etc.
Also as a million people have written, MS probably initially saw DDR3 as the only way to get to 8GB feasibly (these plans may have been laid years ago, 8GB GDDR5 may have seemed impossible back then). And if they wanted to reserve 3GB for non-gaming functions, they needed 8.
if they reveal 12-16 GB of DDR3, the whole ram+eSRAM will cost more tha 8 GB gddr3, don't you agree?
Well just for RAM, it should still be around half as much, to go all the way to 16GB!
Just as 8GB of DDR3 was probably half as expensive as 4GB GDDR5!
16GB DDR3=$60, 8GB GDDR5=$120 in my estimation.
Now what the ESRAM block costs is a different subject.
Are you sure there's not some wiggle room to fit R&D in the production savings across 70 million units?
I realize it's quibbling but could easily end up 100 million or more units, even. 360 is close to 80 million now (I believe it's shipped 77 or 78 million so far, with presumably more to go)
Of course we dont know what will happen, maybe it will be massively popular and do 150m, or get harpooned by PS4 and do 40m...
On 100 million consoles, if you can save $10 per, you just saved 1 billion dollars over the lifetime.
Similarly PS360 usually shipped 12m+ per year in their height, those clamoring for "just $50 price drop" should realize 50X12=$600 million of lost revenue in just one year.