After Effects Crashes When render Is 90% Complete

Your iMac (Late 2015) with 3.3 GHz i5, 32 GB RAM, and AMD Radeon R9 2GB GPU is fairly well-equipped, but After Effects can still crash during 2D compositing due to several factors. Even with CAPS Lock on to minimize preview load and Purge Memory before rendering, After Effects still has high demands for certain compositions, particularly on the GPU and CPU. This crash might happen due to limited GPU VRAM (2GB), which can be insufficient for complex effects or high-resolution projects, as AE often relies on VRAM to accelerate rendering tasks.

To improve stability:
- Try rendering in smaller sections to reduce load.
- Close other applications to free up system resources.
- Check render settings and disk cache in AE; setting disk cache on an SSD can significantly improve performance.

You may not necessarily need a new system template, but upgrading to a GPU with more VRAM, or a newer system if budget allows, would support smoother renders.

Your 27" iMac (Late 2015) has decent specs, but the crashes during rendering in After Effects can be caused by several factors, not necessarily because your hardware is inadequate. Here are some potential reasons and steps to troubleshoot:

### 1. **GPU Limitations:**
- Your AMD Radeon R9 with 2GB of VRAM might be struggling with certain effects or compositions, especially if you're using GPU-accelerated effects or high-resolution assets. After Effects relies heavily on the GPU for some tasks, and 2GB VRAM may not be sufficient for complex scenes.

### 2. **Software Issues:**
- Ensure After Effects and your macOS are up to date. Compatibility issues between different versions of After Effects and macOS could cause instability.
- Try resetting the After Effects preferences by holding down **Shift+Option+Command** while launching the app.

### 3. **Disk Cache and Memory:**
- The CAPS Lock trick to save RAM is outdated and doesn’t offer significant benefits. After Effects uses a disk cache for faster performance, and if the disk cache location is nearly full or on a slow drive, it can lead to crashes. Make sure the disk cache is on a fast drive with plenty of space.
- Consider increasing the amount of RAM allocated to After Effects in the preferences (Edit > Preferences > Memory & Performance).

### 4. **Rendering Settings:**
- If the crashes occur with specific projects or compositions, try lowering the resolution or disabling certain effects to see if it improves stability.
- Alternatively, try rendering in smaller segments or using a different output format.

### 5. **Background Processes:**
- Ensure no other heavy applications or processes are running in the background that might be competing for system resources.

### 6. **Third-Party Plugins:**
- If you’re using any third-party plugins, ensure they are updated and compatible with your current After Effects version. Outdated or incompatible plugins can cause crashes during rendering.

### **Do You Need a Better System?**
- While upgrading your GPU or moving to a system with more VRAM and a more powerful processor could improve performance, you may not need to upgrade your entire system just yet. Try the troubleshooting steps above first.

If the crashes persist after trying these solutions, it might be worth considering a system with a more powerful GPU and better multi-threading capabilities.

Turn off all hardware acceleration, all GPU use, and multiframe rendering. They generally don't make the software faster, and on my last check, it was 22% slower anyway with a varied comp. Macs otherwise are very smart about using disk as RAM when needed, so running out of RAM should not be a worry, generally, unless the software is to blame. All hardware and multi-core stuff in AE takes up more system resources in the interest of squeezing just a few more percentage points of performance (because I guess a refactor is off the table) so definitely keep em off because the venefit is very small for hardware/energy/productivity/system resource costs. Multiframe rendering can be cool, but I find it makes previews unreliable with regards to FPS.

Past that, you might get some luck pulling the entire file into premiere or encoder and trying that way.

Your iMac's specs should generally be sufficient for rendering 2D compositions in After Effects, especially with 32GB of RAM. However, there are several reasons why After Effects might be crashing during renders:

1. Software and Plugin Compatibility

• Update After Effects: Ensure you're using the latest version of After Effects compatible with your system. Older versions might have bugs that can cause crashes during rendering.
• Check Plugins: If you're using third-party plugins, make sure they are updated and compatible with your version of After Effects. Outdated or incompatible plugins can lead to instability.

2. Memory and Performance Settings

• CAPS Lock Myth: Keeping "CAPS Lock" on does not actually save RAM. It only prevents preview rendering in the composition window but doesn't impact the RAM usage during final rendering.
• Memory Allocation: Check your memory settings in After Effects. Make sure After Effects has enough RAM allocated. You can adjust this in the preferences under "Memory & Performance."

3. GPU Limitations

• GPU Performance: Your AMD Radeon R9 2GB GPU may struggle with more complex compositions, especially if they use GPU-intensive effects. You might want to try disabling GPU acceleration in After Effects to see if that stabilizes the rendering process.
• Render Using CPU: If GPU acceleration is causing issues, consider rendering with the CPU only, even though it might take longer.

4. Disk Cache Management

• Disk Cache: Ensure your disk cache has enough free space and is stored on a fast drive. A full or slow disk cache can cause rendering issues. You can clear it through the preferences in the "Media & Disk Cache" settings.
• Purging Memory: While you've already mentioned purging memory, also consider purging the disk cache before rendering and restarting After Effects.

5. Composition Complexity

• Break Down the Composition: If your composition is complex with many layers or high-resolution assets, consider rendering in smaller sections. This can reduce the load on your system and help prevent crashes.

6. System Maintenance

• Update macOS: Ensure your operating system is up to date and that your system is running smoothly. Sometimes, system-level issues can cause instability in applications like After Effects.
• Close Background Applications: Close unnecessary background applications to free up system resources for After Effects.

7. Considering an Upgrade

• When to Upgrade: If you continue to experience issues even after trying these steps, it might be time to consider upgrading your hardware. A newer iMac with a more powerful GPU and more VRAM could handle more demanding After Effects projects with better stability.

• Check System Requirements: Ensure your computer meets After Effects' minimum requirements.
• Update Software: Update After Effects and your operating system to the latest versions.
• Clear Cache: Delete the media cache files through Preferences > Media & Disk Cache.
• Reduce Render Settings: Lower the resolution or use lower-quality settings for a test render.
• Check for Corrupt Files: Identify like wife if specific files or layers are causing the crash.
• Increase RAM Allocation: Adjust RAM allocation in Preferences to optimize performance.
• Disable GPU Acceleration: Turn off GPU acceleration if it's causing issues (Preferences > Previews).
• Update Graphics Drivers: Ensure your graphics card drivers are up-to-date.
• Check for Conflicting Plugins: Disable or update third-party plugins that may be causing conflicts.
• Test with a New Project: Create a new project and attempt rendering to isolate the issue.
• Run as Administrator: Try running After Effects with administrator privileges.
• Consult Support: For persistent issues, consult Adobe support or relevant forums for further assistance.