Linux PowerPC Blender benchmark

[commodorejohn]

Its noteworthy that the X1000 beats a single thread G5.

Unless I'm misreading the chart, the X1000 dual-threaded beats a single-threaded G5; that big-ass bar on the left is for the single-threaded X1000.

[commodorejohn]

In the real world, no one will use 3D software that runs only on the CPU, and wait, when the GPU is able to render the scene almost immediately.

*raises hand* I do. Both because POV-Ray doesn't support OpenCL to begin with, and because Intel chipset video sucks and it'd probably be slower even if it was supported.

But, y'know, that doesn't support your argument, so feel free to claim that it totally doesn't count.

[commodorejohn]

Intel Ivybridge supports OpenCL.

Oh, I'm sure; I just meant that with the general performance of Intel GPUs I wouldn't be surprised to find out that CPU-only rendering was faster anyway :lol:

[commodorejohn]

It has two cores, thus performing much better when rendering is split into two threads (as you can see from the results), just like the new Amiga computer chipset.

There's also the matter of memory speed; the G4s (at least in Macs) only ever had up to a 167MHz non-DDR FSB. Even the slowest G5 machines have much faster front-side buses than that, so anything memory-intensive is going to see a significant boost on the G5.

[commodorejohn]

According to Wikipedia:

The processor has two unidirectional 32-bit double data rate (DDR) buses (one for reads, the other for writes) to the system controller chip (northbridge)  running at one quarter of the processor core speed. The buses also  carry addresses and control signals in addition to data so only a  percentage of the peak bandwidth can be realized (6.4 GB/s at 450 MHz).  As the buses are unidirectional, each direction can realize only half  the aggregate bandwidth, or 3.2 GB/s.

So not exactly optimal (why oh why is there still address/data multiplexing in this day and age!?) but a damn sight better than the G4.