Intel and eDRAM vs GDDR5

[lagokc]

http://anandtech.com/show/6911/inte...usiness-haswell-gt3e-to-integrate-128mb-edram


So if I understand this correctly, Intel is charging $50 extra for a 128MB cache of 64GB/s memory whereas AMD's solution is to give the entire memory interface 54.4GB/s of bandwidth which should increase memory cost around $50.

Somehow I don't see too many people paying what Intel is going to ask for an I7 with the GT3e but not wanting a real graphics card.

 

[ShintaiDK]

GDDR5 gives some challenges with power consumption, traces and the lack of regular SO-DIMMs.

So I would rather turn it around, and say I dont see many laptop designers wanting to use AMDs solution.

Also outside of the PS4. Where do AMD use GDDR5 for their APUs?

 

[lagokc]

GDDR5 gives some challenges with power consumption, traces and the lack of regular SO-DIMMs.

I was under the impression the GDDR5 would be soldered into the board of whatever ultrabook it shipped in? All of the Intel CPUs with eDRAM will be soldered into the board so you're not getting a lot of upgradability either way.

Also what sort of power consumption problems does GDDR5 present? It runs at lower voltage than DDR3 and tends to not generate much heat. Kaveri is supposed to support GDDR5 for its main memory.

 

[Olikan]

eDRAM have crap yields...

that's why....
only high end haswell igps use it, xbox lost money, power7 is expensive as hell

 

[Idontcare]

http://anandtech.com/show/6911/inte...usiness-haswell-gt3e-to-integrate-128mb-edram


So if I understand this correctly, Intel is charging $50 extra for a 128MB cache of 64GB/s memory whereas AMD's solution is to give the entire memory interface 54.4GB/s of bandwidth which should increase memory cost around $50.

Somehow I don't see too many people paying what Intel is going to ask for an I7 with the GT3e but not wanting a real graphics card.

One approach is platform-agnostic, the other requires the entire platform to change.

In 2004 which would you rather have - a platform that required you to buy Rambus ram, or your choice of CPU's that came with varying amounts of on-die cache that could be plugged into a socket on a mobo of your choice?

At least with Intel's approach the only person paying for the eDram is the person who wants it.

With AMD's approach everybody pays for it in buying the platform regardless whether or not they want to use that aspect of the platform.

 

[Chiropteran]

Where do AMD use GDDR5 for their APUs?

Where does Intel use eDRAM? I'm pretty sure neither are used yet in any readily available product, doesn't mean you can't talk about them.

 

[lagokc]

One approach is platform-agnostic, the other requires the entire platform to change.

In 2004 which would you rather have - a platform that required you to buy Rambus ram, or your choice of CPU's that came with varying amounts of on-die cache that could be plugged into a socket on a mobo of your choice?

At least with Intel's approach the only person paying for the eDram is the person who wants it.

With AMD's approach everybody pays for it in buying the platform regardless whether or not they want to use that aspect of the platform.

Kaveri SUPPORTS GDDR5 but does not require it. If you want to maximize the performance of the integrated A10's GPU you buy an ultrabook with GDDR5, if you are going to add a GPU then you buy the version with conventional DDR3 slots. No one is forcing anyone to change platforms.

 

[ShintaiDK]

eDRAM have crap yields...

that's why....
only high end haswell igps use it, xbox lost money, power7 is expensive as hell

PS3 lost more money than Xbox360. And the Xbox Next uses eDRAM as well. The Wii is another user of eDRAM.

I doubt there is "crap yields".

 

[Enigmoid]

GDDR5 is much more power hungry than DDR3. Considering it doubles as system RAM it is going to be running at relatively high speeds constantly (it will downclock from max speed but will still run a a relatively high speed). 4GB is also a lot and will probably consume 2-3 watts more at idle (which will decrease battery life by about 15-20%) and even more at load.

4GB shared system RAM that cannot be ungraded is going to be messy. Thats RAM and VRAM.

AMD uses GDDR5 because they have the experience with it (basically their gpus). Intel uses edram because they have experience with it.

 

[lagokc]

eDRAM have crap yields...

that's why....
only high end haswell igps use it, xbox lost money, power7 is expensive as hell

eDRAM in Haswell requires an extra chip which means one more thing to manufacture. It's not something that's just fused off in the non-eDRAM Haswells.

 

[lagokc]

GDDR5 is much more power hungry than DDR3. Considering it doubles as system RAM it is going to be running at relatively high speeds constantly (it will downclock from max speed but will still run a a relatively high speed). 4GB is also a lot and will probably consume 2-3 watts more at idle (which will decrease battery life by about 15-20%) and even more at load.

4GB shared system RAM that cannot be ungraded is going to be messy. Thats RAM and VRAM.

AMD uses GDDR5 because they have the experience with it (basically their gpus). Intel uses edram because they have experience with it.

Where does this GDDR5 requires more power keep coming from? It's typically a lot more efficient than DDR3 thanks to running at lower voltages. The reason DDR3 GPUs use less power than their GDDR5 version is because the GPU itself consumes less power when it's sitting around waiting on the slow DDR3 memory to feed it data.

 

[Olikan]

PS3 lost more money than Xbox360. And the Xbox Next uses eDRAM as well. The Wii is another user of eDRAM.

I doubt there is "crap yields".

eDRAM is awesome because it's easy to do die shrinks, with almost perferct scaling in size

but it's expensive....initially

According to Petri, eDRAM is only 20% more expensive than normal external memory, and from the price/performance aspect, eDRAM

http://www.firingsquad.com/features/siggraph99/page5.asp

there is a reason why, it only show up in high margin products or with great life spam

 

[Idontcare]

Kaveri SUPPORTS GDDR5 but does not require it. If you want to maximize the performance of the integrated A10's GPU you buy an ultrabook with GDDR5, if you are going to add a GPU then you buy the version with conventional DDR3 slots. No one is forcing anyone to change platforms.

Ah, so the rambus ram comparison is even more apropos then.

 

[Dresdenboy]

Kaveri SUPPORTS GDDR5 but does not require it. If you want to maximize the performance of the integrated A10's GPU you buy an ultrabook with GDDR5, if you are going to add a GPU then you buy the version with conventional DDR3 slots. No one is forcing anyone to change platforms.

Exactly. Just because someone found the GDDR5 support stuff in the BKDG, this doesn't mean, that this will be the only supported type of memory.

This discussion thread might begin to (or is already doing) revolve around a four letter acronym plus a digit.

Then some people come along and talk about the price, board requirements, power consumption of top bin GDDR5 chips (e.g. 7GT/s), while for example the PS4 is using 5.5GT/s chips. There is enough data out there to support power savings achieved using GDDR5.

Further it's not definitely a eDRAM (Intel) vs. GDDR5 (AMD) topic, as AMD is already looking at HBM and stacking too. At least most people agree with higher bandwidth requirements of the ever increasing compute and graphics capabilities. So the removing of this bottleneck by investing more money into removing this bottleneck will allow to make more use of paid, but unused CPU/GPU capabilities.

We might turn the question around: How much faster would a APU/CPU+GPU need to be using DDR3 to reach the same performance? And how much would it cost?

And where is DDR4?

 

[Chiropteran]

Ah, so the rambus ram comparison is even more apropos then.

I don't think the problem with Rambus was ever that Intel was offering a new memory standard. The problem was that Intel was forcing it down our throat, and Rambus ram itself was incredibly overpriced and controlled by an evil corporation of patent trolls. As I recall the actual performance of Rambus, especially on northwood P4 systems, was actually really good, and if it wasn't for the stupid licensing issues and price I think it would have worked out fine.

Is GDDR5 similarly controlled by one evil entity like rambus? I thought it was more of an open standard.

 

[ShintaiDK]

I don't think the problem with Rambus was ever that Intel was offering a new memory standard. The problem was that Intel was forcing it down our throat, and Rambus ram itself was incredibly overpriced and controlled by an evil corporation of patent trolls. As I recall the actual performance of Rambus, especially on northwood P4 systems, was actually really good, and if it wasn't for the stupid licensing issues and price I think it would have worked out fine.

Is GDDR5 similarly controlled by one evil entity like rambus? I thought it was more of an open standard.

I am sure the dram chartel that got convicted didnt help either their anti rambus endeavour.

 

[Idontcare]

I don't think the problem with Rambus was ever that Intel was offering a new memory standard. The problem was that Intel was forcing it down our throat, and Rambus ram itself was incredibly overpriced and controlled by an evil corporation of patent trolls. As I recall the actual performance of Rambus, especially on northwood P4 systems, was actually really good, and if it wasn't for the stupid licensing issues and price I think it would have worked out fine.

Is GDDR5 similarly controlled by one evil entity like rambus? I thought it was more of an open standard.

Do you know who makes GDDR5? It has a price-premium over DDR3 for a reason, and it isn't "lack of volume production"

 

[Chiropteran]

Do you know who makes GDDR5? It has a price-premium over DDR3 for a reason, and it isn't "lack of volume production"

No, I don't, but it doesn't seem excessively expensive so I haven't had a reason to care.

Now, maybe my memory is off, but I thought Rambus RAM was absurdly expensive, like $600 for 2GB, while regular SDR and DDR memory was under $100 for similar amounts. [edit: according to wikipedia I remember wrong, rambus only 2-3X as expensive as regular ram, but it seemed like a lot of money at the time] I don't think I or anyone else would have cared about the licensing and legal issues around Rambus ram if they didn't have such an obvious and direct effect on price.

Now, I can't buy GDDR5 directly to install in my computer, it only comes attached to a video card, but in my experiences it doesn't seem like there is any such similiar absurd pricing. A card with GDDR5 might cost a few $10-$20 more than the bargain version with worse memory, but it doesn't have the obvious direct huge effect on price like Rambus RAM did at the time.

>I am sure the dram chartel that got convicted didnt help either their anti rambus endeavour.

I'm pretty sure that was just a case of a broken clock being right once a day. Or the old throw stuff at a wall and see what sticks. Rambus was trying to sue everybody, I think their company was pretty much all lawyers. They actually won one case out of how many? I don't even know.

 

[Sweepr]

Based on leaked documents, the embedded DRAM will act as a 4th level cache and should work to improve both CPU and GPU performance.

Interesting.

 

[Idontcare]

No, I don't, but it doesn't seem excessively expensive so I haven't had a reason to care.

Now, maybe my memory is off, but I thought Rambus RAM was absurdly expensive, like $600 for 2GB, while regular SDR and DDR memory was under $100 for similar amounts. [edit: according to wikipedia I remember wrong, rambus only 2-3X as expensive as regular ram, but it seemed like a lot of money at the time] I don't think I or anyone else would have cared about the licensing and legal issues around Rambus ram if they didn't have such an obvious and direct effect on price.

Now, I can't buy GDDR5 directly to install in my computer, it only comes attached to a video card, but in my experiences it doesn't seem like there is any such similiar absurd pricing. A card with GDDR5 might cost a few $10-$20 more than the bargain version with worse memory, but it doesn't have the obvious direct huge effect on price like Rambus RAM did at the time.

The only question you've have to ask yourself is "why wasn't this the plan for Llano?"

I give AMD credit for knowing enough about what they do as to assume that they knew in advance that Llano, and its successors, would be critically dependent on ram bandwidth (and limited as such by DDR3).

And yet they opted to do with it anyways instead of doing what they are know proposing to do which is to integrate GDDR5 into the platform.

If the price premium is as minimal as you believe it to be, then why would/did AMD wait until now to integrate their existing GDDR5 memory controller into the APU?

They knew their discrete GPUs needed it, and they knew their APUs would need the latest tech offered in their GPUs, and yet they hamstrung their APUs by avoiding creating a GDDR5 platform until now (not really now, really in the not-so-near future if and when the platform finally reaches newegg).

You are a smart guy, seriously (that isn't sarcasm), so just think about it a bit. It doesn't take much to connect the dots here once you step back and start putting the pieces together.

 

[lagokc]

"If the price premium is as minimal as you believe it to be, then why would/did AMD wait until now to integrate their existing GDDR5 memory controller into the APU?"

As far as I can tell Llano's GPU was intended to be just barely good enough. Its performance does scale well with memory speed (http://www.legitreviews.com/article/2106/6/) getting 33% better performance with DDR3 2133 than DDR3 1333 but isn't utterly crippled. Kaveri will have a much more powerful GPU which will be held back even more by limited memory bandwidth.

 

[Arkadrel]

http://anandtech.com/show/6911/inte...usiness-haswell-gt3e-to-integrate-128mb-edram

Price:
eDram: "rumored to be charging $50 for the eDRAM" + "very good margins"
GDDR5: Sony Rumored to be paying about 110$ for 8 GB of GDDR5 (so 4GB ~55$).

eDram solution : 50$ for eDram + ~30$ for 2x2gb DDR3-1600.
GDDR5 solution : ~55$ ontop of APU price (used as system memory).

Im gonna guess AMD, isnt gonna sell the GDDR5 at the same price it buys it.
So those 55$ ontop of the APU price, could well be near double that for the consumer.

That price wise would probably put AMD at a slight dis-advantage.
(depends on prices they can get. AMD should be useing a cheaper/slower GDDR5 than the PS4 is)


That said, in terms of GPU performance, the AMD APU should slaughter the Intel IGP's with GT3e.
If it can really reach near 7750 levels by makeing a 512sp APU.

 

[lagokc]

"Im gonna guess AMD, isnt gonna sell the GDDR5 at the same price it buys it"

AMD isn't going to be buying it, motherboard/laptop makers will be buying it at good prices and integrating it into their boards.

So you're really looking at:
eDRAM: $50 for eDRAM + $30 for 4GB memory
GDDR5: $55 for 4GB memory

Also you're completely ignoring the fact that the i7 isn't going to be a little more expensive than the A10, the i7 is going to be MASSIVELY more expensive than the top A10. If Intel was going to be using the GT3e in their i3 CPUs it might make sense but an integrated GPU in a hugely expensive i7 is absurd.

 

[krumme]

eDRAM is nice because Intel can control production with marginal cost vs. marginal revenue using its excess production capacity. EDRAM is a perfect product for that.

 

[ShintaiDK]

Also you're completely ignoring the fact that the i7 isn't going to be a little more expensive than the A10, the i7 is going to be MASSIVELY more expensive than the top A10.

Are you forgetting the huge CPU performance difference?