Blender 2.81 and OPTIX

This is a pretty exciting week for Blender users with 2.81 dropping.  As well as a host of new features it offers improved performance when rendering.  I decided to take a look, since performance influences which renderer to use.  In my case, I love the look of cycles but I'm just too impatient.
Using a scene from a project I just finished I decided to compare 2.8 with 2.81 as well as with the latest Studio Ready driver from NVIDIA.

Summary: 
For my limited test scene on my specific computer: 

• 2.81 halved my render time using Eevee.  >54% gain.
• 2.81 cycles with OptiX decreased my render time by a quarter. >25% gain.

Win!

Note: I didn't compare the output images except visually. They look about right, I don't know how different the pixels are, it isn't something I'm that concerned about.  If you need to match footage between versions that might be something you care about. 

Your mileage is going to vary! My scene probably has all kinds of weird stuff in it and for my cycles renders, there is still a lot of noise.  That's partly because I did the project using Eevee so I didn't care about the lighting for Cycles.  The Eevee and Cycles renders look totally different.
My system is an off the shelf HP Omen desktop running Win10 .

• i7 9700F
• 16GB
• RTX 2060

Eevee Performance
Switching from 2.8 to 2.81 gained me a significant performance increase. 
This increase did not change with the new OptiX driver. 

Blender Eevee Time to Render Per Frame for 24 Frames

• 2.8   = 2.6 Seconds
• 2.81 = 1.2 Seconds

Pretty nice lift right?  Basically my Eevee renders now take less than half the time.

Cycles Performance
Blender Cycles Time to Render a Single Frame

• 2.8 = 90 Seconds
• 2.81 =  262 Seconds  <-- this is bad and wrong and I'm a doofuss.

Wait? What? Dur.  Important point here.  You need to go into:
Edit->Preferences-> Cycles Render Devices
and set your preferred rendering system. If you have it set to none which is the default, its going to render on the CPU which will be slow.  

Set your preferences!

Cycles Performance Take 2
By the time I realized the mistake above I'd already installed the latest Studio Ready driver from NVIDIA using GeForce Experience.  I wasn't willing to roll back drivers to test this but I did do render tests on the latest driver with 2.81 with None, CUDA and Optix.

Blender Cycles Time to Render a Single Frame

• 2.8 (Cuda?) = 90 Seconds
• 2.81 (None) = 262 Seconds  <- This implies previous test on old driver wasn't using GPU.
• 2.81 (Cuda) = 89 Seconds
• 2.81 (Optix) =68 Seconds

The interesting result here is 2.81 using Optix. I'm seeing about a 25% reduction in render time which again is definitely worth having.

The scene being used for testing

Disclaimer: 
I used to work at NVIDIA :-)