Encoding HEVC (H.265) fails with out of memory error

Hello, all. I have a 5760x5760 3D-360 timeline with a single 8192x8192 image in it. When I try to export as HEVC (H.265) using AME's software renderer, I get this error. I'm on an 18-core Intel 7980XE, and RTX3090 with 24GB VRAM. Out of memory is highly unlikely.

I've had export issues for the last couple of years. The only way to get high-res HEVC out has been to export a master and use ffmpeg.

AME 15.1 Build 42.

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- Encoding Time: 00:00:00
05/26/2021 01:59:41 PM : Encoding Failed
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Export Error
Error compiling movie.

Out of memory.

Failed to create encoder.

Writing with exporter: HEVC (H.265)
Writing to file: \\?\E:\XXX.mp4
Writing file type: HEVC
Around timecode: 00;00;00;00
Component: HEVC (H.265) of type Exporter
Selector: 9
Error code: 7

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