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This windows tweak HAS to be a joke...

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willkill1337

Member
Joined
Nov 26, 2004
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irc.zirc.org - #octeams
It is possible to boost overall system performance by increasing the IRQ priority of the CMOS real-time clock with the following Registry change.

copy this:

REGEDIT4 [HKEY_LOCAL_MACHINESystemCurrentControlSetControlPriorityControl] ''IRQ8Priority''=dword:00000001

Paste it into a text editor such as Notepad or Wordpad. Save the file as whatever name you want, perhaps boost_irq_priority with a .reg file extension e.g. boost_irq_priority.reg - you can now close the text-editor and simply double-click on the file you just created to enter the information into the registry. To undo this tweak, repeat the procedure but copy this instead into the text file: [HKEY_LOCAL_MACHINESystemCurrentControlSetControlPriorityControl] ''IRQ8Priority''=dword:00000000

You should find that your overall system performance increases from this tweak.


Is this a joke? It seems like it. I have no idea how increasing the priority of the CMOS clock could increase system performance.
 
I can't say if it does anything or not, though I think IRQxPriority is a valid registry entry. Supposedly increasing the priority of a secific IRQ will increase the performance of the devices using that IRQ. One simple way to check the validity of it would be to increase the priority of your Video Card or NIC and see if if FPS or MB/sec are improved from it. Of course, that won't prove wether or not increasing the clock priority helps any, but if the registry tweak dosen't work for OTHER IRQs it certianly wont work for the clock :D

JigPu
 
I may have stumbled across this tweak more or less by accident with my former rig, an NF2 based barton 2500+.

For some odd reason, every second time I booted the machine up, the real-time clock would be totally screwed, 1 hour would pass in 2-3 seconds.

needless to say, if I started a game, NBA LIve 2005, RollerCoaster Tycoon or Unreal Tournament, the games would literally flash acrosss the screen like nothing I have ever seen before.

We're talking "ludicrous speed"... soooo, in theory I could imagine its tweakable, but definately recommendable :cool:

Cheers, Flix
 
i think its changes it back to tieing everything back into clock cycles like an older computers (8086/286 old)

that would explain the time clock and the games
 
So, let me see if I got this straight. Changing the IRQ priority of the C-MOS real time clock clock will allow other components to have more priority.

But to what degree?

I would think that the time clock IRQ only keeps tracks of seconds, meaning that once every second, a request is made to the cpu to run a process which updates the time for your operating system. I don't see how a process this small can't be completed with one clock cycle. One clock cycle every second is practically nothing.
 
rob 119 said:
So, let me see if I got this straight. Changing the IRQ priority of the C-MOS real time clock clock will allow other components to have more priority.

But to what degree?

I would think that the time clock IRQ only keeps tracks of seconds, meaning that once every second, a request is made to the cpu to run a process which updates the time for your operating system. I don't see how a process this small can't be completed with one clock cycle. One clock cycle every second is practically nothing.


thats the thing....if it sets the time clock for example to the same clock of the cpu then ever time theres a cpu clock cycle the secconds will change on your time clock

back long ago they used to tie the programs to the core clock speed and all was well untill it became more thank 60 clock cycles per seccond....kinda think of it as 60 FPS...

but since computers now have WAY more than 60 clock cycles per seccond they no longer tie programs to the clock cycles them selves....now dont ask me how they do it now because thats some complicated crap i dont even know

i just know my old stuff....and my hardware
 
What I think it would do (again, assuming it does anything :D) is to allow for a more stable Real Time Clock (RTC) clock tick. The registry entry would give priority to interrupts (requests for the CPU to drop what it's doing and respond to an event) which are generated by the RTC. The added priority would assure that the clock is updated almost the moment that it requests to be. This could theoretically increase multi-tasking performance, since Windows allows each program/thread to run for X milliseconds before running the next one. With a more stable clock, programs wouldn't accidently hog CPU time because of the RTC not being updated. (Though, the hogging would go both ways, and your foreground program/game/etc would at times get more CPU time than it should too... so I don't see how it would really change anything :rolleyes: )

JigPu
 
I have used this tweak a couple of times on various builds, but I am not sure if it did anything productive. It didn't hurt anything though.
 
If it does anything, which is highly doubtful, the results are less than noticeable contrary to claims...

http://www.pcguide.com/ref/mbsys/res/irq/func_Priority.htm

While at the above site, take a look at the description of what the RTC interrupt is used for. There are several issues with this particular "trick", primarily the fact that RTC is already the third highest priority interrupt...so raising it is would be meaningless. The only things higher are the system timer and the keyboard.
 
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This tweak is old news, I read this like year or more ago on tweaktown, used it a few time also and like someones else said Im not positive it increased anything but it sure didnt hurt anything at all either.
 
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