tag:blogger.com,1999:blog-6569735948568642990.post3687256860791472932..comments2023-07-09T03:36:51.702-04:00Comments on The obsessions of an electronics freak: Mystery (probably) solved; how Samsung pulls off its GPU magic.Electrofreakhttp://www.blogger.com/profile/00831677178752927710noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-6569735948568642990.post-64969978614383419922011-01-16T23:00:31.461-05:002011-01-16T23:00:31.461-05:00Thanks Hugo, I appreciate your critique! You alway...Thanks Hugo, I appreciate your critique! You always seem to turn up when I'm off the mark and I welcome your analysis.<br /><br />In any case, I guess I misunderstood the purpose of the OneDRAM module from what I read in Samsung's documentation. I suppose that mention of improving gaming performance gave me tunnel-vision.<br /><br />I would like to see some information made public about the PowerVR graphics chips themselves... the improved onboard graphics memory would make sense, but I was under the impression that the PowerVR SGX540 used a unified memory architecture. If it is able to use its own dedicated memory, that would completely change the tables.Electrofreakhttps://www.blogger.com/profile/00831677178752927710noreply@blogger.comtag:blogger.com,1999:blog-6569735948568642990.post-21692694481319283922011-01-16T20:13:56.071-05:002011-01-16T20:13:56.071-05:00Nice theory but it makes no sense and is almost ce...Nice theory but it makes no sense and is almost certainly wrong. OneDRAM (as explained in the Samsung page you link to) is a dual-ported RAM to replace a dual-ported SRAM used for communication between two processor packages (i.e. between the modem/baseband processor and the application processor) and some or all of the SDR or DDR DRAM required for the baseband and AP. Nothing on the linked page implies or even suggests that OneDRAM is faster than LPDDR1, and in fact might even be slower. You can clearly see that OneDRAM has a 16 or 32 bit SDR or DDR1 interface on either side that is pin-compatible with commodity LPDDR1. So no, the 128 MB of OneDRAM is not for magic, it is shared by the baseband and the AP and used for the baseband->AP communication. Myth busted (sorry!).<br /><br />I personally suspect the Hummingbird gets such vastly higher GPU benchmark results through more/better/faster on chip GPU cache/tile memory/GPU working memory or whatever. Remember these tile-based GPUs use memory in an entirely different pattern than desktop GPUs and are optimized for minimal off-chip bandwidth by working in small tiles; small enough that you can keep everything in the on-chip (fast) RAM. <br /><br />(My comments are speculation of course, just like yours.)Hugohttps://www.blogger.com/profile/14711489462664363894noreply@blogger.com