CUDA CORE Buyin a card for Cuda

Accelerated Computing CUDA CUDA Programming and Performance
1

This is my second post on this site. I believe I posted first in the wrong forum.
Please help me resolve my confusion. I want to buy a new card to learn CUDA.

I saw on Tiger Direct
MSI GeForce 9500 GT Video Card - 512MB DDR2, PCI Express 2.0, DVI, HDMI, VGA
Stream Processors: 32

Then I wnt to NVIDIA site to verify and it says
CUDA Cores : 32

  1. What is a Cuda Core and how does it relate to stream processors and multi processors?
  2. How many multi processors and how many streaming processors this card has?
  3. do all NVIDIA cards have 8 stream processors in each multi processor?

Thanks…

2
  1. What is a Cuda Core and how does it relate to stream processors and multi processors?

One Multiprocessor = 8 Cuda Cores
(+ 2 Special Function Units (SFU) + instruction decoder + 16kb Shared Memory + more stuff )

  1. How many multi processors and how many streaming processors this card has?

So far “Multi Processor” was used synonymously to Streaming Multiprocessor.

Not sure if a Streaming Processor should be regarded as the same as a Cuda Core.

  1. do all NVIDIA cards have 8 stream processors in each multi processor?

Yes.

I recommend getting a GT 220 (48 CUDA cores, compute capability 1.2) with 512 MB of GDDR3 memory.

Alternatively consider a GT 240 with GDDR5 memory, also a compute 1.2 part.

The choice of the fastest memory option on each card is a little more expensive, but you will have
higher memory bandwidth.

The GTS 250 aren’t bad either, but they are only compute 1.1 cards and have less registers.

For doing serious double precision work, I think a GTX 260 is the entry level.

Christian

3

Thank you for the fast response,

I am still confused about what a CUDA Core means. Is it one multi processor or it is one streaming processor?

Take the GeForce 9500 GT as an example. It has 32 CUDA Cores. What does that mean?

If a CUDA Core = a Multi processor, then this card has 32 * 8 = 256 stream processors.
If a CUDA Core = a Stream Processor, then this card has 32 stream processors and 32 / 8 = 4 Multi processors.

Which one is it?

Thanks…

4

The latter. That card has 4MP, each containing 8 cores = 32 total.

5

Thanks…

It is clear now.