I'm no expert, but I think more than these things go into it (and I suspect way more than a 2x IPC bump, but that's guesswork). Also more cache and I'm sure more and faster memory.
The point I was making is that even if one assumes the worst about the PowerPC and the best about the Snapdragon, the comparison doesn't make any sense.
Even if the IPC were FOUR times that of the PowerPC and we accepted the other assumptions in favor of the Snapdragon, that'd make one quad core Snapdragon 344 times faster than the slowest RAD750, so if four or more RAD750s have ever been sent to space, then that'd make the Snapdragon LESS than 100 times faster than just four RAD750s. That's not taking in to account all of the other CPUs used in space missions.
Larger caches and faster memory are necessary to just maintain the IPC - they don't mean that the Snapdragon is faster per clock by virtue of those alone.
I have a 600 MHz PowerPC 750 system (original iMac with Sonnet accelerator) and a Cortex-A15 system (the Cortex-A15 is a 32 bit ARM from around the same time as the Snapdragon 801, and which has better IPC than the Snapdragon), and I can say that the IPC of the Cortex-A15 is much closer to 1.5 times than 2 times that of the PowerPC.
johnklos|2 years ago
Even if the IPC were FOUR times that of the PowerPC and we accepted the other assumptions in favor of the Snapdragon, that'd make one quad core Snapdragon 344 times faster than the slowest RAD750, so if four or more RAD750s have ever been sent to space, then that'd make the Snapdragon LESS than 100 times faster than just four RAD750s. That's not taking in to account all of the other CPUs used in space missions.
Larger caches and faster memory are necessary to just maintain the IPC - they don't mean that the Snapdragon is faster per clock by virtue of those alone.
I have a 600 MHz PowerPC 750 system (original iMac with Sonnet accelerator) and a Cortex-A15 system (the Cortex-A15 is a 32 bit ARM from around the same time as the Snapdragon 801, and which has better IPC than the Snapdragon), and I can say that the IPC of the Cortex-A15 is much closer to 1.5 times than 2 times that of the PowerPC.