This isn't used anywhere.

comfy/ldm/models/diffusion/ddim.py

@@ -33,7 +33,6 @@ class DDIMSampler(object):
         assert alphas_cumprod.shape[0] == self.ddpm_num_timesteps, 'alphas have to be defined for each timestep'
         to_torch = lambda x: x.clone().detach().to(torch.float32).to(self.device)
 
-        self.register_buffer('betas', to_torch(self.model.betas))
         self.register_buffer('alphas_cumprod', to_torch(alphas_cumprod))
         self.register_buffer('alphas_cumprod_prev', to_torch(self.model.alphas_cumprod_prev))
 
@@ -195,7 +194,7 @@ class DDIMSampler(object):
                       temperature=1., noise_dropout=0., score_corrector=None, corrector_kwargs=None,
                       unconditional_guidance_scale=1., unconditional_conditioning=None, dynamic_threshold=None,
                       ucg_schedule=None, denoise_function=None, extra_args=None, to_zero=True, end_step=None, disable_pbar=False):
-        device = self.model.betas.device
+        device = self.model.alphas_cumprod.device
         b = shape[0]
         if x_T is None:
             img = torch.randn(shape, device=device)