Alan NV8A
Fri, 05 Feb 2010 14:12:53 -0800
On 02/05/10 04:51 pm, James E Watts wrote:
...I thought I would pass on a performance enhancer for Vista and Windows 7 users. I was fortunate to be able to find a PCI slot to put my TI Firewire card in that didn't share IRQ's with anything else, but theres a tweak that will allow you to set your 1394 PCI card IRQ to have number one priority. It's called IRQpriority and the link will have a step by step guide. Caution, it does require editing your registry and adding a key, but this guide will step you through it with screen shots. http://helpdeskgeek.com/windows-vista-tips/manage-irq-settings-windows-vista-7/
I immediately looked this up because I thought it might help me too, although I have WinXP rather than Vista or Win7. This is what I found:
'Myth - "Adjusting the Priority of IRQs especially IRQ 8 improves system performance."
Reality - "IRQs don't even HAVE a concept of "priority" in the NT family; they do have something called "IRQL" (interrupt request level) associated with them. But the interval timer interrupt is already assigned a higher IRQL than any I/O devices, second only to the inter-processor interrupt used in an MP machine. The NT family of OSes don't even use the real-time clock (IRQ 8) for time keeping in the first place! They use programmable interval timer (8254, on IRQ 0) for driving system time keeping, CPU time accounting, and so on. IRQ 8 is used for profiling, but profiling is almost never turned on except in very rare development environments. Even if it was possible it doesn't even make sense why adjusting the real-time clock priority would boost performance? The real-time clock is associated with time keeping not CPU frequency. I would not be surprised if this originated in an overclocking forum somewhere. This "tweak" can be found in most XP all-in-one tweaking applications. This is a perfect example of why they are not recommended."'
73 Alan NV8A _______________________________________________ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/