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Posted 08 May 2012 - 10:33
Posted 08 May 2012 - 10:48
Posted 08 May 2012 - 11:16
Posted 08 May 2012 - 11:26
Posted 08 May 2012 - 11:27
Enabling HPET in BIOS is just half way of enabling HPET, it needs to be enabled in OS too, and in a way that it's the only timer used.
By default windows uses combination of TSC+ACPI timers, not matter if HPET is enabled in BIOS.
TSC+LAPICs Low performance (slow timers + syncing)
LAPICs low performance (slow timer - no syncing)
TSC+HPET medium performance (slow and fast timer + syncing)
HPET high performance (fast timer - no syncing)
HPET + platformclock=true will give you best timer resolution, frame rate and lowest DPC latency.
You can test timer ratio and QueryPerformanceFrequency with WinTimerTester 1.1 http://www.mediafire...xzo9n84d8lze9nb
The higher the QueryPerformanceFrequency is the better is performance. You only get high frequency with HPET. The other timers will give you significantly less frequency. Also note that if your ratio is not 1.0000 you are off set (or you have wrongly OC'ed), enable HPET and you should be without sync problems.
If you ever want to go back to default timers admin cmd:
bcdedit /deletevalue useplatformclock
Varying depending on setup, one should get increase up to +30 FPS and from the between.Online games is a good example of boost from HPET.
Posted 08 May 2012 - 11:35
Posted 08 May 2012 - 11:43
Without changing any settings in the BIOS or the OS, and with HPET enabled in the BIOS as normal I get this
Posted 08 May 2012 - 11:45
^Because if you enable HPET in BIOS you will mix it with other timers and CPU needs to sync between them. You need to force HPET only and reboot. Mixing HPET with other timers is not good, but using HPET only will give you best performance. People don't know about that Windows needs to be forced to use HPET only - that's why the bios setting alone can undergrade their performance.
bcdedit /set useplatformclock true (then reboot) enable HPET
bcdedit /deletevalue useplatformclock (then reboot) disable HPET
Posted 08 May 2012 - 12:02
Posted 08 May 2012 - 12:11
Posted 08 May 2012 - 12:13
Mouse pointer has a ghost trail now like I am using a cheap LCD with 20ms response rate
Posted 08 May 2012 - 12:16
Posted 08 May 2012 - 12:21
Enabling HPET in BIOS mixes HPET with other timers - needing the CPU sync between the timers resulting in compromised performance. If WIndows is forced to use HPET only (in bios and os) it in modern system results in higher performance, higher FPS and better DPC.
Test and try what suits you.
Posted 08 May 2012 - 12:27