Core Ultra 300: Panther Lake to get fewer cores but more waste heat

Intel's processor generation Arrow Lake aka Core Ultra 200 is not yet fully on the market, but the first detailed information about its successor Panther Lake is already making the rounds. Panther Lake will be released before the end of the year – following the new naming scheme, probably as Core Ultra 300 – and for the first time will feature chips that roll off the production line in the brand new 18A manufacturing process. The latter is Intel's hope to catch up with market leader TSMC in terms of production technology. At Arrow Lake, TSMC produces all the chiplets except for the interposer, which connects the individual parts together.

At Panther Lake, not only the production of the CPU chiplet is now to be relocated to its own fabs: According to a data sheet published by leaker Jaykihn, Intel will also be making coarser changes to the number and composition of CPU cores (performance, efficiency, low-power efficiency). Since Meteor Lake, there have been the expansion stages H (Core Ultra 100H: 6 P cores, 8 E cores, 2 LP-E cores) and the derived and slimmed-down U (Core Ultra 100U: 2 P cores, 8 E cores, 2 LP-E cores). Despite new microarchitectures for the respective cores, their number was adopted 1:1 for Core Ultra 200H and Core Ultra 200U. The Core Ultra 200HX was added at the top end with 8 P and 16 E cores, but without any LP-E cores.

Slimming measures

According to Jaykihn, Panther Lake only has 4 P cores plus 8 E cores as the H level, i.e. a third fewer P cores. As the reduced number of P-cores means that there is hardly any room left to change the composition for the smaller U-stage, Jaykihn says that these will be slimmed down even more radically in other areas: they will no longer have any E-cores at all. It is not clear from the published material whether there will still be LP E-cores to compensate for the deletion. However, our gut feeling tends to be no, because LP-E cores already play no role in the HX models at the top end or in Lunar Lake (Core Ultra 200V) for particularly mobile notebooks.

It is also unclear what this means in terms of the expected computing power. According to Jaykihn, Intel is turning another adjusting screw at the same time: The nominal waste heat (PL1) is to remain the same as before at 25 watts, but PL2 will increase from 55 to 64 watts. PL2 is the value that the CPUs are allowed to consume in their turbo frequencies as long as the cooling systems of the notebooks still have reserves and other parameters such as a limit value regarding the permissible maximum current are not exceeded. The slimmed-down U-stage should nominally remain at 15 watts PL1.

It is also not yet known whether Panther Lake will see the return of hyperthreading, which turns one real core into two virtual cores. In Meteor Lake, the P-cores still used this technology, but Intel has turned off the function in Arrow Lake.

Tick-tock, but different

And then there is the open question of which market segments Panther Lake is actually intended for. Meteor Lake clearly focused on notebooks. Desktop PCs, on the other hand, had to wait until Arrow Lake to get Intel CPUs made up of chiplets, while mobile-specific innovations had to be sought with a magnifying glass. For notebooks, the focus has instead shifted to Lunar Lake, which was developed completely outside of the main series.

Panther Lake has to bring the advantages of Lunar Lake, including an NPU suitable for Copilot+ and a powerful integrated graphics unit, back into the main series, preferably with production in Intel's own fabs, as described above. Compared to Lunar Lake (4P+4E), Panther Lake (4P+8E) should be a clear step forward. And who knows what else Intel's engineers have up their sleeves, as they are clearly committed to chiplets: If you combine two CPU chiplets of 4P+8E, for example, you end up with 8P+16E again, which would correspond exactly to the previous HX expansion stages.

This is exactly what the Panther Lake successor Nova Lake, which is likely to become the Core Ultra 400 at some point, is supposed to be: Rumor mongers are talking about up to 48 CPU cores (16P+32E), which will be assembled from two 8P+16E chiplets. However, this is something for powerful desktop PCs; for notebooks, 8P+16E should remain the maximum. There is no mention of LP-E cores with Nova Lake, but again there is talk of 4 P cores without E-core support as the smallest U level. (mue)