[AMDocn] Windows 8 Benchmark Records No Longer Accepted At HWBOT / RTC clock bug

[Atomfix]

As the result of weekend-time research, the HWBOT staff has decided to invalidate all benchmark records established with the Windows8 operating system. Due to severe validity problems with the Windows8 real time clock (“RTC”), benchmarks results achieved with Windows8 cannot be trusted. The main problem lies with the RTC being affected when over- or underclocking under the operating system. The operating system uses the RTC as reference clock, and benchmarks use it to reference (benchmark) time.

Source

If your benching on Windows 8, you should stop right now, your benches won't be valid

[kalniel]

I don't get it. I thought all motherboards had a crystal RTC.

[Atomfix]

I don't get it. I thought all motherboards had a crystal RTC.

Not sure :/ Never heard of a "Crystal RTC" until now

[kalniel]

Not sure :/ Never heard of a "Crystal RTC" until now

It's the standard way of keeping a reference time signal - you have a bit of quartz or whatever crystal that you apply a voltage to (powered by the CMOS battery when computer is off) - it will only vibrate at a fixed frequency, so gives you a time reference. The other source that's used in AC devices is the frequency of AC itself, but PCs are DC devices so don't use that. If you don't have an accurate RTC then you couldn't even play back music properly.

edit: or maybe it's not actually standard these days :/ Thought it was part of Intel southbridges for most chipsets.

edit2: It is.

App Note: Intel® ICH Family Real Time Clock Under Test Conditions

Background: External Real Time Clock (RTC) Circuit

Intel® chipsets using an Intel® I/O Controller Hub (ICH) family component use a crystal circuit to generate a low-swing 32 kHz input sine wave. This input is amplified and driven back to the crystal circuit via the RTCX2 signal. Internal to the ICHn (any member of the ICH family), the RTCX1 signal is amplified to drive internal logic as well as generate a free running full swing clock output for system use. This output pin of the ICHn is called SUSCLK.

The crystal network employs R1, C1, and C2 to generate the 32.768 kHz sine wave. Actual values for these components are dependent on the crystal component specification, trace lengths on the motherboard, and the crystal’s load capacitance.

pdf: http://www.intel.com/content/dam/doc...tions-note.pdf