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Old 08-28-2010, 04:46 PM   #280
JFAMD
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Join Date: May 2009
Posts: 565
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Quote:
Originally Posted by Soleron View Post
Loss of throughput compared to two fully seperate integer cores. Not compared to Phenom II.

Imagine:

2 Phenom cores = 100% IPC

2 BD modules, 1 core per module = 130% IPC

1 BD module, 2 cores per module = 120% IPC

JF has also made two other claims with regards to performance:

1. Interlagos will perform 50% better than MC in the same thermals
2. IPC increase for single-threaded workloads will be "a lot" more than 17%
Actually I said 3 things:
1. Interlagos will perform 50% better than MC in the same thermals
2. IPC would be higher
3. Increase for single-threaded workloads will be "a lot" more than 17%

I have made no statements that I am aware of about IPC with a percentage implied because I don't know what the IPC is, all I was told is that it would be higher. If I did say IPC would be higher by a percentage, it was a mistake; ocasionally those things happen to us humans.

The ~17% number (or the 12.5% or 12.8% numbers) are all tied to people trying to reverse engineer the 50% number (performance of 16-core vs. 12-core) for a single thread. I have said repeatedly that trying to pull single thread performance from a statement about a fully loaded and fully utilized processor is not going to be accurate. It is like trying to figure out travel times at 3AM based on rush hour traffic.

Based on Scali's treatment recently I just don't feel like I need to respond to him at all. Let him think whatever he wants, it is more convenient for him that way.
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