What has biggest effect on rendering times?

Coming from that 2019 Intel MacBook Pro, basically everything about a new MacBook Pro will decrease your render times by a lot, because the Apple Silicon CPU, GPU, and encoders are all so much better now. But not equally, so what will be the most bang-for-buck will depend on what kind of projects you render. 

If your projects are simpler, like a couple of tracks with mostly fades and cuts, you could get a recent MacBook Pro with the Pro-level processor (for example, an M4 Pro processor, not the base M4). The reason to get the Pro and not the base is that the base processor is the only one with a CPU that has more Efficiency cores than Performance cores, meaning it’s designed more for battery life than faster rendering. So the Pro processor should be your baseline for video editing productivity. Also the base level is the only level with only one cooling fan; the Pro and up have two fans. If you can, stick with 32GB of Unified Memory or more. This combination should render your projects far faster than your Intel Mac ever could.

If your projects are significantly more complicated, like lots of tracks (e.g. multicam), transitions, and effects, or you edit at higher than 4K, you might benefit from moving up from a Pro processor to the Max or Ultra. Those levels are more expensive, but you get many more GPU cores (Premiere, After Effects, and Media Encoder use the GPU more than ever), and also a second Media Engine to accelerate video codec decoding (for playback) and encoding (for rendering).

The M4 is available at the base, Pro, and Max levels; the most recent Ultra is available for M3 only. The M5 was just released, but so far only at the base level. Even the base level of the M5 would be a huge upgrade over your Intel Mac, but some of us who are considering upgrades are waiting for the Pro level and up of the M5 to be released and then we’ll upgrade to one of those.

Personally, I’m waiting to upgrade to the more powerful GPU of the still unreleased M5 Pro or Max, based on how Adobe has been increasing its use of GPU acceleration. Also, the newer features based on machine learning and generative AI are completely dependent on the GPU — not the CPU — for high performance.

Also, you may hear a lot of hype about the Apple Neural Engine in current Macs, which is a neural processing engine (NPU) that’s supposed to help accelerate machine learning/AI features. Some Windows PCs have an NPU as well, especially Copilot+ PCs. But I just want to mention that at this time at least, the NPU has zero effect on your purchase decision because I cannot name a single feature in any Adobe software that uses the Apple Neural Engine on the Mac. (It’s not much better in Windows.)

Since you cannot upgrade anything internally in that MacBook Pro, your only solution is a brand new Apple Silicon MacBook. You can no longer purchase a new Intel CPU-powered Mac-anything. And among the Apple Silicon Macs, buy the one with the best balance between the CPU, RAM and internal SSD storage that you can afford. That may mean that you may have to sacrifice the CPU slightly in order to get a sufficient amount of RAM and a sufficiently large internal SSD for your workflow needs. You would not want to go whole hog on the CPU only to be forced into making serious sacrifices in the amount of RAM and having to settle for an insufficiently-sized internal SSD. A GPU with more cores within the same Apple Silicon family (say, between two different GPU offerings within the Apple M4 Max group) is nice to have, but not really necessary given the minimal difference in GPU rendering performance between the two versions.

Also, @DoYouLikeHam:

I forgot to mention this in my other reply.  Since you would be upgrading from an Intel based MacBook Pro to an Apple Silicon based MacBook Pro, Apple Migration Assistant is okay to use for settings and documents but do not use Migration Assistant for applications.  Do a clean download and install of your Adobe applications.

Heya @DoYouLikeHam:

If I had to pick one component, I'd say CPU has the biggest effect on render time; however, our machine's performance is a result of the sum of the parts (CPU, GPU, system bus, RAM, storage media, and on newer machines NPU).

Coming from your model MacBook Pro, I'd pick a 16-inch or 14-inch MacBook Pro M4 Max, but the M3 Max, M2 Max, and even M1 Max should provide a good improvement.  If not the Max, then M4 Pro, M3 Pro, or M2 Pro.

I would also try to go with 32GB/1TB as the base for video editing and motion graphics, but give serious consideration to increasing each.

Here's a great After Effects benchmark that really tests a system (note: I'm not sure how well it would run on your configuration):
The Ultimate Free After Effects Speed Test File

https://youtu.be/bCgnAoJLVHc?si=PiRp02NSIBWXjdcJ

Here are results that I've gotten on some of my computers:

16-inch MacBook Pro M4 Max 128GB/4TB

4 Min, 20 Sec

    Application: After Effects v25.2.2.2

    OS: macOS v15.3.1, RAM: 128.00 GB GB, CPUs (logical): 16

    Apple M4 Max; 128GB RAM, 16 Cores (12 performance and 4 efficiency) with 40 GPU Cores (Metal 3)

    16-inch MacBook Pro (Mac16,5)

2019 Mac Pro 192GB/4TB

12 Min, 7 Sec

    Application: After Effects v24.6.6.1

    OS: macOS v13.7.4, RAM: 192.00 GB GB, CPUs (logical): 32

    2019 Mac Pro

    3.2 GHz 16-Core Intel Xeon W

    AMD Radeon Pro Vega II 32 GB

    192 GB 2933 MHz DDR4

16-inch MacBook Pro M1 Max 32GB/1TB

13 Min, 21 Sec

    10 Cores (8 performance and 2 efficiency) with 32 GPU Cores (Metal 3)

    16-inch MacBook Pro (MacBook Pro 18,2))

2017 iMac pro 64GB/2TB

16 Min, 38 Sec

    Application: After Effects v25.2.2.2

    OS: macOS v13.7.4, RAM: 64.00 GB GB, CPUs (logical): 20

    2017 iMac Pro (iMacPro1,1)

    3 GHz 10-Core Intel Xeon W

    Radeon Pro Vega 56 8 GB

    64 GB 2666 MHz DDR4

HP zBook Studio 16 inch G10 Mobile Workstation 13th Gen Intel Core i9-13900H, 2600 MHz, 14 Cores 32GB/1TB Microsoft Windows 11 Pro

20 Min, 25 Sec

    Application: After Effects v25.2.2.2

    OS: Windows v10.0.22631, RAM: 31.64 GB, CPUs (logical): 20

   HP zBook Studio 10 16-inch

   System Model      HP zBook Studio 16 inch G10 Mobile Workstation PC

   Processor   13th Gen Intel(R) Core(TM) i9-13900H, 2600 Mhz, 14 Core(s), 20 Logical Processor(s)

   Intel Iris Xe Graphics/NVIDIA GeForce RTX 4070 Laptop GPU

   DDR5 PC5-44800 5600MHz Non-ECC SODIMM

13-inch MacBook Pro M1 16GB/512GB

28Min, 3 Sec

- Warren

@Warren Heaton10841144 

@RjL190365 

Moved to video hardware forum.