CPU Usage

[toxic]

since getiing a x2 3800 a few months back..i have noticed that during intensive applications the CPU Usage only ever shows as arround 50% for each CPU...is there any reason for this? It is currently overclocked to 2.6Ghz.

Cheers

 

[Agent WD40]

Does it ever go above 50%?

If not the reason is because the task manager sees both cores as one. So when one core is running flat out its effictivly only using 50% of the overall CPU power.

Hope that helps.

Agent.

 

[toxic]

it does sometimes....just when I run the likes of prime95 and CPU burn etc. when the cpu utilisation should be 100% task manager and similar reporting programs only show 50-60% utiliastion whereas before with a single core 64 bit AMD cpu these loads would alsways be at 100...or very close too. I just wondered if this was correct and that the dual core was operating properly. Running cpu burn in the pic attached shows rainmeter and task manager only showing mid 50's for CPU where I would expect it to be 100%.....

man how do u attach pics to this forum?????

Cheers

 

[Agent WD40]

hehe, I use photobucket to upload my pics.

So to attach pics you've gotta upload them to a web site and post the link on the forums.

www.photobucket.com if you wanna regester...

Agent.

 

[Mikey1280]

or imageshack if you dont want to register

 

[spookywillow]

if your only running 1 instance of prime then it will only reach around 60%.

you need to run 2 instances of prime testing small FTT's to see it use 100%

 

[Corasik]

CPU Usage on XP is an average of all cores, and Prime95 is single threaded, so it only uses one core. The other is just doing a few minor 'XP' background chores.

Of course being dual core, if it makes you happy you can run a Prime/Seti/Whatever pleases you, while playing a game on the other core, without any performance loss whatsoever.

Dual core mostly improves multitasking at the moment, although in the future programmers of applications and games will likely use more multithreaded code which allows a single program to use both cores efficiently.

 

[squiffy]

Load up two copies of CPU burn and both cores will be at 100%, or if you use shrink with full priority mode again both at 100%.

Remember if you were doing this on a single core it'll be at 100%, and be unusable. With the dual cores you can have one core fully loaded (windows will of course split it 50/50) so each core will be at 50%, total 50% be the same speed as one core at 100% (if both same frequency CPU) But it will be faster doing the process if both cores are at 100% (but will have to leave the computer to do it's thing until it's finished)

 

[toxic]

Ahh yes...i see and understand now. 2 sets of cpu burn puts full load on the dual CPU. Thanks for explaining.

So i guess that when you are gaming...full load is put on only one of the CPU's right...while the other CPU just sits there operating other windows programs etc. Is there a way of telling windows to dedicate both CPU's to one program only...for instance during video encoding so that you can complete the task faster????

 

[toxic]

or even better still...allocate a CPU to whatever program you want...or does windows just do this automatically?

cheers guys

 

[spookywillow]

applications will only use both cores if its written to do so, you cant tell a single threaded app to use both cos it wont.

you can set "affinity" by right clicking a process in task manager, select "affinity" and uncheck a core so it only uses a specific one but windows does a good enough job of this by itself. only do this is programs feel funny or games stutter.

as for video encoding i use vegas 4 and it wont use both cores so i guess its not multi threaded although i thought it would have been, but on a plus side i can still do other stuff at normal speed without the rendering slowing my pc to a halt

 

[toxic]

cool...thats what i thought...just though there mught have been programs on the go that lets you select both processors at same time.

Thanks for the help....