15" rMBP with dGPU for gaming

[Mr MM]

So is it the same buying an old retina 650m ?
Also,I was wondering .
New Retina Haswell sports the new thunderbolt 2 which is as far i can read
not even close a real pci express 8x-16 ,(consider i'm not a proof here so feel free to correct me),
but with the entry MacBookPro starting at about 2000€ and with no discrete,
having to pay +600 euros to have a 750m (sorry for the long period),
do you find acceptable to spend that money on an MLogic external solution
like this one http://www.mlogic.com/products/mlink-x
which starts at 499$ able to load a 3/4 graphic Gpu card?
I mean a 3/4 gtx 760 could do the "trick"?
In this way i can program my expense step by step,
first the MBPro,then the Malogic,then the Gpu card,even if hate that 750m policy which leads me to not accept that price for a discrete.
I mean,which kind of performance would be able to achieve a solution like this?
On par with a 750m?Lower?Higher by far or not?
Thanks for your attention and your posts which are helping me choosing which machine to buy (an old 650m,a no discrete one or a new 750m..which frankly could burn an hole in my wallet).
Consider also that i'm a casual gamer and i use my lap just to work while to game i do prefer consoles.
Here's a thread about Mlogic https://forums.macrumors.com/threads/1593386/

TB2 is different from TB

they are backwards compatible and will work at the rated maximum speed of the slower component.

thus waiting for TB2 and getting a external gpu using the older protocol isn't going to provide you with better gaming.

anyway, the problem here is to get the external gpu to work with windows, because it depends on the switching of gpus, that is disabled on bootcamp. thus the best way to go, is to get the iris pro only model.

in terms of performance, you are going to achieve much of the external gpu performance, but the higher you go, the higher the loss is. for example in tests done sometime ago a 560ti had the same performance as the 6970, to which shouldn't happen if there wasn't a limitation in bandwidth

and just to be clear here

the 640m LE/ 640m/ 645m/ 650m/ 660m/ 730m/ 740m/ 750m/ 755m are the same gpu. they use the same core. they vary on that they can use either DDR3 or GDDR5, being the latter faster by 10-15%. with the 730m we also have half the bandwidth options, which jump from the usual 128bit to the 64bit in some models

the 700m series introduced the cripple boost 2.0, which is basically several thermal tiers, the problem lies that they use the lowest possible thermal tier to design cooling, thus not giving you the full performance.

aside that we enter the problem of you couldn't stress at 100% both the cpu and the gpu on the 2012 rmbp, throttling through heat was achieved on the higher end cpu models, throttling through lack of power was still much present as it always was

 

[theCraigLaw]

I have the new rMBP base model with Iris Pro obviously. I have a bit of a decision whether to save $100 and go for an older refurbished one with twice the SSD space and of course, the 650m. It's whether the gaming performance benefit is enough to warrant sacrificing the extra battery life and PCIe drive speed benefits.

Decisions, decisions. Waiting for Anandtech...

 

[HurryKayne]

TB2 is different from TB

they are backwards compatible and will work at the rated maximum speed of the slower component.

thus waiting for TB2 and getting a external gpu using the older protocol isn't going to provide you with better gaming.

anyway, the problem here is to get the external gpu to work with windows, because it depends on the switching of gpus, that is disabled on bootcamp. thus the best way to go, is to get the iris pro only model.

in terms of performance, you are going to achieve much of the external gpu performance, but the higher you go, the higher the loss is. for example in tests done sometime ago a 560ti had the same performance as the 6970, to which shouldn't happen if there wasn't a limitation in bandwidth

and just to be clear here

the 640m LE/ 640m/ 645m/ 650m/ 660m/ 730m/ 740m/ 750m/ 755m are the same gpu. they use the same core. they vary on that they can use either DDR3 or GDDR5, being the latter faster by 10-15%. with the 730m we also have half the bandwidth options, which jump from the usual 128bit to the 64bit in some models

the 700m series introduced the cripple boost 2.0, which is basically several thermal tiers, the problem lies that they use the lowest possible thermal tier to design cooling, thus not giving you the full performance.

aside that we enter the problem of you couldn't stress at 100% both the cpu and the gpu on the 2012 rmbp, throttling through heat was achieved on the higher end cpu models, throttling through lack of power was still much present as it always was

You're right.I personally find this time a little hard to decide,because i don't wanna spend 600 euro more but the Iris Pro has the same (?) or its close the performances of the old 650m ,so i can buy an old 15 plus 650 m but it won't have the Thunderbolt 2,but i need a machine to work..gosh..i think i'm little confused this time.
Even more Broadwell will be released in late 2014 and next Thunderbolt "3" at 50Gbps will be in the 2015 so..i think i will need a laptop a little bit before..
and this while i like to game but i'm a casual one and so no need to have a thunderbolt external card waiting at home but my consoles.
Ok.Haswell Iris 15 is probably the best i can buy now.
thanks for clearing my ideas

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That's a solution I am going to be testing in the future following the guides at tech inferno, but it'll be more of a project than trying to be serious about it. Gaming on a laptop is a subpar experience in any case, so the best solution is always to have a gaming rig. But I find it an exciting proof of concept thing which could deliver quite good results: talk is about 85 to 95% of the card's normal performance through TB2 - considering the mobile versions of cards can't reach anywhere near that (a 780MX probably cannot reach the performance of a desktop 580 GTX even today) makes it a wonderful idea.

For the occasional boom boom and if you're not that much into gaming, the MBP is alright, even the Iris Pro one. Then there's the money and value, that part is very personal and it's a lot harder for someone with a tighter income to dive in for a MBP than something else, although in many cases it will pay for itself quickly (plus the resale value is great). Then again, I buy my Macs for work and then some gaming, for real gaming there's the PC and always desktop, no compromises there unlike with all laptops.

Finally, as much as some are into saying the 750M offering is the same as the 650M, take that with a grain of salt especially with all the benchmarks out there that don't make it clear wether they're using the DDR5 or DDR3 version, plus the OEM's clocking, it's very clear they're not the same card. It's the same chip and a rebrand, that much is true, but the first most observable thing is it has 1 more GB of VRAM, and you don't need anyone to see if that's true or not, it's right there in the spec sheet. Other than that, minor changes like clock and increased bandwidth. Initial impressions are that the card is under clocked, however I would suggest waiting for Anand's thorough review which will let us know the ins and outs.

Thanks for the gentle reply^^