Windows 8 RTC Bug Found, Benchmark Results Still Banned At HWBot

Subject: General Tech | August 27, 2013 - 07:59 PM |
Tagged: windows 8, overclocking, hwbot

Earlier this month, competitive overclocking website HWBot banned benchmark results that come from systems that use Microsoft’s latest Windows 8 operating system. Unfortunately, Microsoft made a compromise and choose to use an internal software timer rather than a hardware-based Real Time Clock (RTC) to ensure compatibility with budget and embedded systems that skip such hardware to cut costs. Ocaholic’s Christian Ney has further analyzed the RTC bug and posted an article on the bug and how to fix it.

HWBot’s issue with Windows 8 is that users are able to artificially inflate benchmark scores by down-clocking the CPU BCLK using software in Windows 8 rather than via the BIOS (which does not effect results). Under Windows 8, when down-clocking using software tools, the amount of time the benchmark measures does not match up with the amount of time that has actually passed--and would be correctly reported by a hardware timer. Unfortunately, Windows 8’s Real Time Clock references the QueryPerformanceCounter (QPC) which is able to read a hardware timer but does not by default on Intel-based platforms. On the other side of things, AMD-based systems are less effected by this bug, but users could turn off the default hardware timer to cause similar artificial benchmark score inflation (the system is able to push out more calculations and/or frames per second in a reported amount of time that is less than the actual time it took to complete the benchmark, giving users an artificially higher score).

For Intel users, the bug can reportedly be fixed by opening up an administrator command prompt and typing the following command.

“bcdedit /set {current} useplatformclock Yes”

While it is nice to see the analysis and a fix for the bug, HWBot is still not allowing Windows 8 benchmark scores. An update on HWBot's original blog post states that all new Windows 8 results except those from non-overclockable notebooks are banned. Further, any existing benchmarks from Windows 8 systems that seem out of line or are either world records or top scores will be removed from the site. Windows 8 benchmarks with AMD hardware are also banned.

It appears that, although there is a fix for the RTC bug, until HWBot can somehow verify that users have either implemented the fix on Intel systems or not changed the default settings for AMD systems, benchmark results from Windows 8 can still not be trusted. Here’s hoping some method will become available to allow for that necessary verification.

Source: HWBot