Elpida put XDR on EOL, is Sony abandoning XDR?

[Crossbar]

I noticed today that Elpida put all of their XDR chips on their EOL list, even the last 1 Gbit units, which is the size currently used in the PS3.

Samsung is now the only source of XDR chips and they put their old 512 Mbit units on EOL as well so they just offer the 1 Gbit units.

I have seen no announcement of anyone else entering the XDR business and I find it highly unlikely that Sony will rely on only one source for XDR memories. So this begs the question: Is Sony abandoning XDR for their next die shrink of Cell and moving to GDDR5?
IBM already made a version of Cell that used DDR2 so it´s not like Cell is designed around XDR. The only technical hindrance as I see it, is if it could break BC with current games for some reason?

The current crop of low voltage GDDR5 seems like a good fit with Cell. Courtesey of Samsung.

As I see it they could also easily replace the GDDR3 memory (4 pcs 512 Mbit units) of the RSX with GDDR5 (2 pcs 1 Gbit units) and cutting the bus from 128 bits to 64 bits as well in the process.

Leaving the XDR niche memory and going with standard GDDR5 memory units would probably lower the price of the memory in PS3. XDR never took off in the mass market beside the PS3, letting it go at this stage would make sense in my opinion.

What do you think?

 

[rpg.314]

I don't think they will do that.

 

[upnorthsox]

They'd need a redesign of the FlexIO, and I'm not sure that Sony would save any money with a switch to GDDR5 either.

What I think, is what is self evident, when Nvidia chose GDDR5 instead of XDR it was game over for XDR.

Elphida must believe that Sony's contract with Samsung will run out this gen. This may be an indicator that this gen is closer to over than we are led to believe though.

 

[AlphaWolf]

I'd be surprised if Sony hasn't secured their supply of ram for the foreseeable future, and just because a supplier lists it EOL doesn't mean they won't continue to manufacture under a current contract.

 

[rpg.314]

What I think, is what is self evident, when Nvidia chose GDDR5 instead of XDR it was game over for XDR.

When they got kicked out of jedec, it was game over for rambus.

 

[Crossbar]

They'd need a redesign of the FlexIO, and I'm not sure that Sony would save any money with a switch to GDDR5 either.

No need to do that, the PowerXCell kept the FlexIO when moving to DDR2.

Why do you think that GDDR5, would cost more?

Elphida must believe that Sony's contract with Samsung will run out this gen. This may be an indicator that this gen is closer to over than we are led to believe though.

That´s another theory, but I doubt they will cease manufacture PS3s anytime soon.

 

[Crossbar]

I'd be surprised if Sony hasn't secured their supply of ram for the foreseeable future, and just because a supplier lists it EOL doesn't mean they won't continue to manufacture under a current contract.

Yeah, I know, but it probably means that the production line is burried when that contract runs out, but securing supply cost money. How far can Sony predict the future?

What I also find disturbing is that Elpida actually removed the press release from their archive where they announced the 1 Gbit XDR unit. It feels a bit like history falsification.

 

[Crossbar]

When they got kicked out of jedec, it was game over for rambus.

Isn´t that like 15 years ago? But yeah I guess they never really recovered from that scandal. That may still be a reason why foundries are reluctant to support Rambus memories.

 

[max-pain]

As I see it they could also easily replace the GDDR3 memory (4 pcs 512 Mbit units) of the RSX with GDDR5 (2 pcs 1 Gbit units) and cutting the bus from 128 bits to 64 bits as well in the process.

For that bandwidth (20.8 GB/s) it only needs one 2Gb GDDR5 chip with 32 bit bus.

But of course it's not that simple...

 

[Shifty Geezer]

Isn´t that like 15 years ago? But yeah I guess they never really recovered from that scandal. That may still be a reason why foundries are reluctant to support Rambus memories.

Lack of a market is probably the biggest reason.

Who's making RDRAM for the PS2?

 

[upnorthsox]

When they got kicked out of jedec, it was game over for rambus.

Well it can be awkward to find out that the only reason you've been invited to the party is because you'd be bringing your stash.

 

[Crossbar]

Lack of a market is probably the biggest reason.

That goes two ways, if the JEDEC companies got competeing technolgy that will give them better margins, why market Rambus technology. If Rambus had their own production facilities things might look different.

Who's making RDRAM for the PS2?

Does it still use RDRAM? The latest models (SCPH-7900x and later) use an ASIC incorporating EE+GS+system memory according to wiki.

 

[upnorthsox]

No need to do that, the PowerXCell kept the FlexIO when moving to DDR2.

Kept it yea, but with a redesign:

The MIC provides the interface between the EIB and main storage. The X2D logic in the PowerXCell 8i
processor replaces the XIO macros in the Cell Broadband Engine™ (CBE). The X2D logic interfaces to the
existing MIC - XIO and provides the necessary translation logic to convert the XDR packets to equivalent
DDR2 memory commands.

Why do you think that GDDR5, would cost more?.

Because it does now? GDDR5 is pretty niche itself at the moment.

That´s another theory, but I doubt they will cease manufacture PS3s anytime soon.

Yep definitely speculation on my part.

 

[Shifty Geezer]

Does it still use RDRAM? The latest models (SCPH-7900x and later) use an ASIC incorporating EE+GS+system memory according to wiki.

Well at some point Sony switched, and presumably they'll do something the same. Some custom...chip...thing?? We'd just need to find out about suppliers of RDRAM to see how things worked out for PS2.

 

[Crossbar]

Kept it yea, but with a redesign:

Kind of unavoidable.

Because it does now? GDDR5 is pretty niche itself at the moment.

There are at least 3 different manufacturers who currently have GDDR5 memory listed as mass production, no one has ever listed XDR memory as mass production.
I think you are in a better position for shopping around and getting a good price of standard GDDR5 units than if you have to ask someone to start up a production line for your XDR order, but that is just my gut feeling.

 

[Crossbar]

Well at some point Sony switched, and presumably they'll do something the same. Some custom...chip...thing?? We'd just need to find out about suppliers of RDRAM to see how things worked out for PS2.

A custom 32 MB (by today standards slow) dram chip is probably pretty cheap and manageable to wire to a custom EE+GS in that thing.

I believe 256 MB of high speed DRAM is probably still far away from a custom solution, it will probably go through a couple of die shrinks until it it gets as cheap as it can get. If someone else can pay for those die shrinks there are a lot of money to save.

 

[Shifty Geezer]

A custom 32 MB (by today standards slow) dram chip is probably pretty cheap and manageable to wire to a custom EE+GS in that thing.

Sure, but at some point it wasn't. And at some point RDRAM must have been hard to come by, as again only Sony were using it (AFAIK). Oh no, weren't Ninteod using it in GC too? Although GC's custom was nothing compared to PS2's. Still, at some point RDRAM would have been dropped. However Sony got around the lack of an RDRAM supplier for PS2, they should theoretically be able to get around that for PS3, unless the problem has occured much earlier for PS3. And at the moment Samsung at still supplying, so Sony can probably get a few more years or even a stockpile until they can fabricate a new solution. The introduction of PS4 won't mitigate the need for XDR for PS3 which should still sell as the entry level machine and in other markets for some years afterwards, same as PS1 and PS2.

 

[Grall]

And at some point RDRAM must have been hard to come by, as again only Sony were using it (AFAIK). Oh no, weren't Ninteod using it in GC too?

Nintendo64 used first-gen RDRAM (which was embarrassingly slow, but had incredibly low pin-count for its highly theoretical bandwidth, which must be why they used it anyway).

Gamecube used Mosys 1T SRAM memory (just like the Wii), both for embedded and external RAM.

PS2 used 2nd generation DRDRAM, which was much faster than the original incarnation. DRDRAM was also used in some professional gear, like a number of routers and switches and stuff like that I believe.

 

[Shifty Geezer]

Sorry, yeah. It was N64 that used RDRAM. These consoles using non-standard RAMs have always managed to find a supplier, so I dare say this isn't anything that'll impact PS3. At worst it'll impact Sony's profitabilty if they are fixed into one supplier keeping prices high.

 

[V3]

Why switch to GDDR5 though ? If they make the switch it'll be to DDR3. But Sony probably have all the XDR they'll need till the end of PS3 life by now.