importance of # stream processors? 8800GT vs 9600GT


I’m searching which card to use. 9600GT vs 8800GT
The 8800GT has 112 stream processors, and the 9600GT only 64.
Does the number of stream processors affects the performance for cuda applications?

Yep, it makes the biggest difference of all the different variables as I understand it.

Think of a Streaming Multiprocessor as a piston in your engine.

A V12 is better than a V8 :geek:

However your gasoline costs will be outrageous.


So what does ‘gasoline’ signify in your simile?

energy consumption.

I can’t imagine a case where energy consumption is comparatively more expensive with a bigger card, if you need CUDA acceleration to a significant problem to begin with.

Edit: Hope that didn’t sound rude. Just thinking out loud.

depends on how big your gas tank (power supply) is

But 9600GT and 8800GT, being both G92, have about the same power consumption (95W vs 105W, according to wiki).

Btw, this comes out to 1c/hr for computing. (Which is actually $100/yr if you run it 24/7/365.)

Maybe I’m wrong here, but I’m pretty sure the amount of power your system uses is dependent on the internals and NOT the wattage rating of your PSU. Two systems that are exactly the same except for the wattage of the power supply should use the same amount of electricity. Realize that when I say the “same amount” I recognize that there are tiny differences due to efficiencies, but for all intents and purposes, these should be equal.

EDIT – because I did some goofy math the with above post and (almost) made a fool out of myself. Note to self, there are 365 days in a year, NOT 365 weeks :)

I was more hinting to the fact that if you buy a GTX280 and you have a 400 Watts power supply, you will definitely need a new one - adding a lot to the total costs.

The wattage rating may have an influence as well: The power efficiency of the PSU somewhat depends on the load that you draw. A high power PSU with low current draw will be quite inefficient. I wouldn’t advise drawing just 300 Watts from a 1500 Watt PSU. Running close to the PSU’s rated power may also degrate the efficiency somewhat, just don’t ask me why. I could explain to you how a cell phone works, however.