Hi. I’m looking to upgrade my current i7-3770 machine to something a bit more modern. I’m having a really hard time choosing between the Ryzen 9950X and the Core 9 Ultra 285k, so I was hoping maybe someone with more recent PC building experience could help me out.
Some background on my requirements:
- I’m looking at these higher-tier CPUs despite probably 80% of my usage being pretty undemanding web browsing and word processing. However, a lot of the software I use regularly is compiled from source and I do devops-type stuff as a hobby, so I’m looking to improve compile times, run multiple virtual machines, run fuzzing campaigns and improve the viability of playing with computationally-intensive experiments.
- Power (and, given the above, idle and near-idle power in particular) is a key concern for me. I live in a locale that gets pretty warm during the summer, and I’m a little scared of going back to something like the Phenom II X6 which just made my living space unbearably hot.
- I don’t really care about video game performance, so that’s not a reason for me to rule out the 285k or for 3D VCache to be an appealing trade-off. Further, I don’t use Windows, so I’m not bothered by whatever performance issues the 285k has over there at the moment.
- I’m also not bothered by Intel’s refusal to commit to LGA 1851. If it’s another twelve years before my next CPU upgrade, AM5 won’t provide a better upgrade path.
Here’s where I’m at trying to evaluate the two:
9950X pro | 9950X con | 285k pro | 285k con |
---|---|---|---|
slight edge in geomean productivity benchmark scores, but a mixed bag | |||
16 full-fat cores | only 8 P-cores | ||
2-SMT, 32 threads | no SMT, 24 threads | ||
only 16 cores | 24 cores | ||
full width AVX-512 – looks like fun to program with! | no AVX-512, E-core AVX double-pumped, AVX seems to cause throttling? | ||
AM5 supports ECC memory – probably good for the mdraid array | no ECC support on consumer chipsets, no workstation boards currently available | ||
AM5 seems very picky about memory configuration | seems comparatively less picky – simpler to get right and maybe simplifies future memory upgrades? | ||
XMP/EXPO makes idle power consumption worse? | |||
More efficient – default power cap at 200W | Less efficient – default power cap at 250W | ||
Worse idle power | Better idle power – at least 20W lower? | ||
Cheaper, by about $200 AUD |
This leaves me with several questions:
- I don’t know what to make of the 16 vs 8 P-cores, 32 vs 24 threads, 16 vs 24 cores comparisons.
- I like to leave my computer on overnight, in which case the 285k wouldn’t just be idle but should be in an S0ix state. Would this meaningfully improve the idle power edge?
- Is 20-30W lower idle power actually a meaningful difference in terms of heat output?
- Would it make sense to have a more conservative power limit for summer, or would the performance impact be severe enough to warrant looking at another processor?
- How do these chips compare power-wise when not idle or pegged, but when doing lighter, bursty tasks like web browsing?
- Are there any other power gotchas I should be aware of? For instance, I was surprised to learn that apparently Samsung NVMe drives have issues with ASPM.
I know this is a long post, but if you got this far, thanks! I look forward to hearing about your experiences or any advice you have to offer.