| zarx said: Link? The largest GDDR5 chips I can find reference to are 2Gbit. http://www.elpida.com/en/products/gddr5.html, http://www.skhynix.com/products/graphics/graphics.jsp?info.ramCategory=&info.ramKind=26&info.eol=NOT&posMap=graphicsGDDR5, http://www.samsung.com/global/business/semiconductor/product/graphic-dram/catalogue So unless you have a source that 4Gbit GDDR memory chips will be available in the next few months. |
You are right. Even Hynix lists 2Gb (256MB) GDDR5 as the maximum density (http://www.hynix.com/products/graphics/graphics.jsp?info.ramCategory=&info.ramKind=26&info.eol=NOT&den=2Gb&posMap=graphicsGDDR5)
Even the Asus Ares 2 that costs $1,600 had to use 24 GDDR5 chips to reach 6144MB of GDDR5 (or 256MB per chip):
http://www.techpowerup.com/reviews/ASUS/ARES_II/3.html
"The problem here is one of memory density - at the moment 256MB of [GDDR5] RAM is the highest amount of memory that can be packed onto a single chip. Multiple chips can be stacked together and accessed in parallel, but then the memory bus that connects them to the rest of the system becomes a lot more complex - and more expensive - to make. At 2GB we're already looking at eight memory modules crammed onto the mainboard, and 4GB would see that doubled to what could be an unmanageable 16, bringing with it the necessity for an expensive 256-bit or even a 512-bit memory bus."
Orbis: The Next-Gen PlayStation Takes Shape
http://www.gamesindustry.biz/articles/digitalfoundry-assessing-playstation-orbis-rumours
Sounds like 4GB of GDDR5 for PS4 might be optimistic in 2013 now that I think about it. But it's not impossible because you could fit 8 chips around the Pitcairn GPU and the 256-bit native bus on the Pitcairn HD7870 (HD7970M) is perfect for this. 8 chips on the front of the board, and 8 on the back. It would be expensive though.
If PS4 uses off-the-shelf PC components, I think it's more reasonable it uses 4GB of DDR3 and 2GB of GDDR5 for the GPU. That type of setup more closely resembles how a PC functions.
