Amy: The WLAN driver version you cite should end in .278 not .78. Not that most of us don't already know that, but... :)

Hi Amy,

I've had an opportuniy to run some tests with the new BIOS and quiet/balanced/performance modes and have some very intersting results but a question at the end.

For testing purposes I ran msconfig.exe and restarted by machine in diagnostic mode so all extraneous services had been stopped. I then ran a number of different tests using each of the modes selected in the BIOS. Here are the results:

1. Visual Studio Solution Build (each time I clean the build.) This is a real-world test of the sort of thing I do throughout the day and usually drives the fans mental (but not on my 3 year old Yoga 2 Pro which is as quiet as a mouse)

• Quiet Mode: Run 1 - 1m 25s, Run - 1m 06s, Run 3 - 1m 06s, Run 4 - 1m 06s
• Balanced Mode: Run 1 - 1m 25s, Run 2 - 1m 05s, Run 3 - 1m 05s, Run 4 - 1m 06s
• Conclusion - unfortunately I didn't run this in performance mode but the timings really were exactly the same but I did think the quiet mode was noticeably quieter throughout the tests.

2. Performance Test from which I only ran the CPU benchmark

• Quiet Mode: Run 1 : 5752, Run 2: 5787, Run 3: 5792
• Balanced Mode: Run 1: 5758, Run 2: 5752, Run 3: 5856
• Performance Mode: Run 1: 5768
• Conclusion - again no noticeable difference.

3. Blender Raytrace using demo file Fishy Cat

• Quiet Mode: 1m 45s
• Balanced 2m 14s
• Performance: 2m 08s
• Conclusion - now we're talking... but wait Quiet mode is not only quiet but much faster!! What's going on! This is when I started running HWMonitor to see what was going on in the CPU and discovered why Quiet is so much better and problem should be always on. Here's what I found:
• Quiet Mode: Max 87C and clock speed flipping between 3029Mhz and 3192Mhz
• Balanced Mode: Max 96C and clock speed shifting between 399Mhz and 3495Mhz
• Performance Mode: much the same as balanced but seems to spend less time at 399Mhz.
• Theory - I think Quiet focuses on keeping the temperature down by controlling the Mhz but that just happens to end up much faster - a bit like saying 'slow and steady wins the race'. Performance/Balanced however try for more raw power but spending longer throttling back to 399Mhz given the critical temperatures - a bit like sprinting and running out of puff and taking longer to recover.

So, great news, Quiet seems like a real win.

However, when I used msconfig.exe to get back to normal and have all my services running again I discovered a couple of weird things:

• CPU Benchmark now returned 5508 and 5350 in two separate runs
• Blender now took 2mins 8secs to render
• Theory - I might have thought that other processes were simply consuming processor time making these take longer (I did change the CPU benchmark to run in a higher priority to try and mitigate for this.) However, what I noticed when running blender was the temperature now hovered at 71C and the Mhz oscillated between 2583Mhz and 2896Mhz both a lot less than previously. I also tried changing the power plan from balanced to performance but that made no difference.

Question

So I'm left with a question. Is there a service that's limiting the performance of the CPU? And whilst I'm here - is this anything to do with the constant logging of the following in the event log:

The speed of processor 3 in group 0 is being limited by system firmware. The processor has been in this reduced performance state for 71 seconds since the last report.

which is being logged by Microsoft-Windows-Kernel-Processor-Power.

And finally

Amy, I hope my findings above are useful to you. My initial feelings are you've done some great work on getting this BIOS written and I'm very grateful. I still get the feeling the fans themselves are a little noisy (especially compared to the Yoga 2 Pro) but at least now they're not spinning up quite so fast now.