- HX = ???
- H = high performance (typically 45W TDP)
- HS = also high performance, but with a lower TDP (typically 35W TDP)
- U = standard part (typically 15W TDP)
We can reasonably surmise that the Ryzen 9 5900HX (assuming the chip is real) is a high-performance part, because of the "H" designation. The "X" designation adds more to the mix—probably an unlocked multiplier, or maybe an even higher TDP for additional clocks/performance.
Anyway, here is the listing...
According to the listing, the unannounced CPU resides inside an ASUS ROG Zephyrus GX551QS laptop. it has 8 cores and 16 threads, with a 3.3GHz base clock and 4.6GHz boost clock, along with 16MB of L3 cache. For reference, the current generation Ryzen 9 4900H has 8 cores and 16 threads, with a 3.3GHz base clock and 4.4GHz max boost clock, and half the L3 cache (8MB).
Additionally, this will probably end up being a Cezanne part, meaning it is based on Zen 3. Rumor has it AMD will split is Ryzen 5000 series into Zen 3 (Cezanne) and Zen 2 (Lucienne) parts, which I think will be needlessly confusing, but it is what it is.
As to the performance, it posted a 1,429 single-core score and 6,912 multi-core score. One of the most recent entries for a Ryzen 9 4900H, which resides inside an ASUS TUF Gaming laptop, has it posting a 1,176 single-core score and 6,733 multi-core score.
This is all early data, of course, so do not read too much into the results. The bigger takeaway here is that AMD could have a new suffix under its sleeve, and it will be interesting to see what exactly it is used for.