Describe the bug
The new xformers optimization has something that makes it so that when given the same parameters for generation the same image won't be generated, see examples below. It seems to be less noticeable given more steps.

To Reproduce
Steps to reproduce the behavior:

1. Activate xformers enhancement by adding --xformers to launch params
2. Generate 'a robot dog' with seed 1, euler a, and 30 steps
3. Generate it again and notice that the result is slightly different

Expected behavior
Generations should be consistent given the same parameters.

Screenshots

Prompt: A robot dog
Seed: 1, CFG: 7

With xformers:

Without xformers:

With xformers + differences highlighted:

Without xformers + consistency highlighted:

Desktop (please complete the following information):

• OS: Windows 10
• Browser: Chrome
• Commit revision: b458fa4

Additional context
Perhaps this is just the nature of the optimization?