[Lenovo ZUK Z2 (Plus) Guides, News, & Discussion] Avan7:
Hello and welcome!

This morning I began wandering the XDA ZUK Z2 forums, looking at all these new threads and posts. I'm really impressed with all the progress for the Z2 that developers have been making lately. So I decided to try a few new ROMs.

I have always found really interesting to test new ROMs, set them up, install everything back and then use the ROM for a few days to see how everything goes... Only to find out that a new feature has been released or a new version of the ROM I'm currently using and the process begins again, it's really cool :victory:

So today I picked a few ROMs, and decided to try them all, run a few benchs and write down the results. At the end I thought I could share the data gathered and perhaps we could get some idea of how these ROMs perform.

So the general process was the next:

Wipe everything but internal.

Flash ROM and ROM alone, no GAPPs, Magisk or MODs.

Wipe Dalvik and Cache (dev recommendation).

Shutdown from recovery, boot, install benchmark apps and restart.

Clear recents and begin benchmarks.

Notes:

TWRP used was latest official version.

Baseband is the latest official baseband for the chinese Z2.

ROM version was the latest as of yesterday.

Kept the phone above 40% battery, so battery charging was needed between ROM flashing from time to time.

Cooled phone between benchmarks, as to prevent throttling from affecting the benchmarks, however didn't add cooling when benchmarking.

Alright then! Let's get down to it!

Data:

SSE: Sling Shot Extreme.

SSE scores: Overall scrore, graphics score, physics score. Ditto for Vulkan.

Geekbench 4 scores: Single core, multi core.

Geekbench 4 COM: Compute benchmark.

Now let's talk a bit about these numbers. As you can see Oreo ROMs get higher scores in both 3DMark and Geekbench benchmarks, with Cosmic getting the higher score in the Sling Shot Extreme OpenGL benchmark and Cypher in the Vulkan variant, although not by much. In Geekbench Jaguar leads with the higher score in both the single core and multi core test. Now look at every Oreo multi core score, it is higher than its Nougat counterpart, I wonder if this is in part because of the drivers or OS optimizations, however I also wonder how this shows, if it show at all, in real world usage.

I would like to note that if I'm not mistaken Jaguar had increased CPU frequencies, not sure about the GPU though, and that could be one factor for the increased scores, however OMNI got really close to Jaguar and again, if I'm not mistaken, Jaguar is based on OMNI. I would like to point that as the day passed the room temperature increased (hot day), so take the temp thresholds with a grain of salt. The battery percentage loss found in the table is that which 3DMark reported in the OpenGL test.

One thing is that even when the numbers varies from ROM to ROM the difference is not that huge (around 12% max in the multi core CPU test), and most importantly... how this translates to real world usage?

So perhaps you noticed the last column, Dolphin. I decided to install the latest Dolphin version and run The Legend of Zelda - Wind Waker intro screen and write down the highest and lowest FPS reported by the emulator. What we find is that the scores do not always reflect into the emulator FPS. Also there is a 'DoT' in almost all ROMs, what does that means? Well DoT stands for slowDown on Touch, yeah it makes no sense but it stuck. When running the emulator if the phone detects no input from the touch screen the FPS slow down by approximately 40%, that's what DoT means, I had to keep touching the screen to get full FPS, only on Citrus this was not the case, and I was getting full FPS with no input whatsoever.

So what all this means? Surely we always like to see higher numbers, I know do. But with time I have found that higher numbers are not necessarily better, or that it does not translate to better performance, battery life or SoT, stability, features, etc., for example in Oreo ROMs I always liked more how colors showed in the screen, even though we have KCAL in Nougat ROMs too. Also I ran these benchmarks only once, so they are not one hundred percent accurate. Usually more runs = more score accuracy, so take these with a grain of salt.

For fun I decided to OC the CPU when using Citrus 3.5, set Adreno boost to high (honestly don't know what it does just that it boosts something related to the GPU I guess haha) and even when the benchmarks didn't improve that much (actually it got a worse multi core CPU score) I got better Dolphin FPS, and that just proves my point.

And that was just one real world test which I think it's heavier on the CPU. I would like to test an intensive GPU game and get some data on that. Also, numbers don't say much when talking about customization and features, so to really feel a ROM you have to test it out yourself.

It would have been awesome if I had have the time to test more ROMs or kernels, I just picked some ROMs from the Telegram group and some here randomly. But! That means that there is more out there for you to try out! As I said in a post this morning: That just means you have a lot of options to choose from and have fun installing, customizing and using the ROMs in your phone.

So yeah, had fun doing this and wanted to share. A HUGE thanks to all the developers out there! Thank you for giving life to our device! :highfive:

EDIT. Please forgive my english, I'm still learning :)