New Mobile GPUs not New at All

Many of us were hoping that the first batch of new mobile graphics chips from AMD that are being rolled out right now (in the new Envy laptops, among others) would be built on the new 28nm process and bring some genuine improvements to the mid-range segment. Those expectations were thoroughly squashed when it was revealed that both AMD and NVIDIA are repeating their old tactic of simply renaming old GPUs and passing them off as new models. In other words, the “new” graphics chips are not 28nm but based on the old 40nm process. In fact the first HD 7000M GPUs are almost or entirely indistinguishable from the current HD 6000M series.

The Whistler and Seymore core are reused with nothing but superficial changes. The mainstream Radeon HD 7400M card is actually a GeForce 6470M with 160 stream processors, 8 texture units and four ROPs. It can either be used with GDDR5 or GDDR3 memory via a 64-bit memory bus; the 7500M is really a 6630M with 480 stream processors, 24 texture units and 8 ROPs. There is an option to use either GDDR5 and DDR3 memory over a 64-bit bus.

Finally, the Radeon HD 7600M–one that we thought would be a new and interesting chip–is a Radeon HD 6750M with 480 stream processors, 24 texture units and 8 ROPs. Again with the possibility for both GDDR5 and DDR3, but an 128-bit memory bus. The only apparent difference is that the three “new” graphics cards can be used with either DDR3 and GDDR5.

And NVIDIA’s first parts in the 600M series are getting the same treatment, but in this case it looks like there are no changes whatsoever–just new names for old parts. The GeForce 610M is replacing the 520MX and the 630M is replacing the 540M in name only. A very small difference can be spotted in the GeForce 635M that replaces the GT 555M that currently powers the Alienware M14x. The improvement is a marginally higher memory clock.

Read the rest at the source: AnandTech