RSX ist ...

[Jesus]

Geklaut aus dem B3D Forum, vielleich fällt euch ja mehr ein: :rolleyes:

AT E3, 136 shader ops per cycle were presented for RSX, which can be equated to 136 instructions/cycle.

Also 51 billion DOT products per second were presented for CELL+RSX combined. From above it was deduced that RSX would have 52 DOTS/cycle --> 52 vec4 units.

http://www.beyond3d.com/forum/showpost.php?p=484757&postcount=119

An over-clocked 7800 will have 56 DOTS/cycle and therefore not agree with the numbers for 52 DOTS/cycle. However it does agree with 136 instructions/cycle.

We know that each PS pipes have 2 vec4 units and each VS pipes have 1 vec4 unit. Also PS pipes are 5-issue and VS pipes are 2 -issue. I.e.


PS issue rate * PS pipes + VS issue rate * VS pipes = 136

2*PS pipes + 1* VS pipes = 52

PS pipes > 0 and integer
VS pipes > 0 and integer

Now solving for,

PS issue rate = 5,6,7
VS issue rate = 2,3,4

-----------------VS issue 2-------VS issue 3----------VS issue 4----------VS issue 5
PS issue 5----- FAIL--------------12 VS:20 PS--------4 VS:24 PS---------FAIL
PS issue 6----- 20 VS:16 PS-----FAIL-----------------FAIL-----------------FAIL
PS issue 7----- FAIL--------------FAIL-----------------FAIL-----------------FAIL

So in order to get a valid solution to the above equations, either the PS pipes are modified for 6-issue or the VS pipes are modified for 3-issue or 4-issue.

Summary

Option A

8 VS pipes, 2-issue
24 PS pipes, 5-issue

Modified 7800 and basically disagrees with the dot product numbers from E3.

Option B

12 VS pipes, 3-issue
20 PS pipes, 5-issue

Option C

4 VS pipes, 4-issue
24 PS pipes 5-issue

Option D

20 VS pipes, 2-issue
16 PS pipes, 6-issue

Option E

Other!

Please specify...




Auch noch intressant:

http://www.graphicshardware.org/presentations/heirich-presentation-gh05.pdf

[Coda]

Auch noch intressant:

http://www.graphicshardware.org/presentations/heirich-presentation-gh05.pdfDas ist übelstes Compilerzeuch. Ich glaube das wird hier wirklich nur die hartgesottenen interessieren ;)
Im Prinzip geht es darum einen Shader automatisch auf mehrere Passes zu zerlegen, wenn die Resourcen nicht mehr reichen.

Zum RSX: Mich würde es wundern, wenn nVIDIA viel an der Pipeline geändert hat, aber man weiß es nicht.

[Botcruscher]

Aber durchaus verständlich. Irgendwo muss die Effizens ja gesteigert werden. Erinnert mich irgendwie an die Gerüchte von diesen "Super-Pipelines".