And to get right to the point… Let’s look at the GPU performance.
While the Radeon HD 5450 has the same number of shader processors as the E-350 (80), they run faster and it has a dedicated 1.6GHz memory bus to feed it. The E-350 has to share memory bandwidth between the two Bobcat cores and the 80 SPs, severely limiting its performance potential.
Exactly what I’ve been saying all along: Even if you use a GPU of the exact same specs as a discrete card, it’s not going to be as fast, because of the shared memory bottlenecking the GPU.
Even in completely GPU-limited situations, it still doesn’t perform like a discrete card:
Compared to the Radeon HD 5450 the 6310 offers between 66 – 69% of its performance in our GPU bound tests. The performance reduction is entirely due to the 6310’s limited memory bandwidth being shared with the dual Bobcat cores on-die.
This is just a low-end Fusion chip, but the differences between high-end Fusion and discrete cards will only be larger, as the shared memory will only become more of a bottleneck compared to the discrete cards.
So although this is nice for a low-end desktop or notebook chip, people who thought they were going to get the performance of midrange discrete GPUs will be disappointed.