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View Full Version : Encoding: GPU v CPU




Superman07
Oct 22, 2008, 11:07 AM
I'm not an expert in this area, so it's hard for me to tell between the GPU and CPU which plays the most important role. Perhaps it's dependent on the way the software is written, I'm not sure.

However, as I've read through the threads here I've noticed some discission of difference in times, but I can't tell why.

For example: Mac Pros are beating out the iMac, which in turn beat the Mac Books.

Now I know this may seem obvious and "duh", and more is better, but how much more and what is it worth - both in terms of dollars and time?

Let's assume the processor speed is the same, what benefit would one see from the 256mb iMac card v the 512mb card? What then if you bump the processor to the 3.06ghz option? Likewise for the new entry Mac Book with the 9400M to the dedicated 9600 unit.



Eidorian
Oct 22, 2008, 11:09 AM
I don't know of any software on OS X that uses GPU encoding, yet.

mrgreen4242
Oct 22, 2008, 11:18 AM
For video encoding in OSX, at the moment, it's all about CPU speed, including both raw CPU power and the front side bus speed. Harddrive and disc drive speed can play a roll in this if your CPU is fast enough as well, depending on the source and destination of your encode.

Memory has a limited effect on encode speed, and GPU, at this time, has none.

dynaflash
Oct 22, 2008, 02:39 PM
Speaking for HB, its all about cpu, number of (including cores) and clock speed. HB uses little ram actually. a c2d is awesome, and a quad is better yet (due to multi-threading). there are diminishing returns above that though, like a quad vs. an octo. GPU will do nothing for encoding with HB.

Eidorian
Oct 22, 2008, 02:42 PM
Speaking for HB, its all about cpu, number of (including cores) and clock speed. HB uses little ram actually. a c2d is awesome, and a quad is better yet (due to multi-threading). there are diminishing returns above that though, like a quad vs. an octo. GPU will do nothing for encoding with HB.This is where I suggest running multiple instances of Handbrake.

dynaflash
Oct 22, 2008, 04:19 PM
This is where I suggest running multiple instances of Handbrake.

Do *not* try this with HB Snapshot 3 (macgui version) or above. Each instance would try to use the same queue plist and disaster would ensue. You have been warned ;)