720QM Question & oddities when running super pi..anyone else noticed?

[MrMatt]

I have an HP dv8t laptop, with the 720QM i7 in it. As I understand it, it runs underclocked, and can get up to 2.8 when under load. However when i run Super Pi it never gets that high. It will touch 2.5 briefly, but even with super Pi running it hovers around 1 Ghz. Is there any reason for this?

 

[PCTC2]

In Windows, do you have your power settings set to "Power Saver"? If so, you'll need to bump it to "High Performance" to get Turbo to kick in properly.

 

[MrMatt]

Seems to be working, running at 2.4 now with Super PI going full blast



edit: The odd thing though, when I select performance, the speed doesn't go back down once the processor load is reduced. So it goes to about 2.7 with Super Pi on, and fluctuates in that area. After super Pi finishes, and with no other processes running, it still stays in that area.

There's a default power scheme (From HP) that I can use, with that one it runs around 2.4 when running Super Pi, and afterward it goes back to underclocking itself.


edit 2: Some oddities with this processor: When running Super Pi it actually beats my Phenom x4 965 (3.4GhZ). For instance at 2M the x4 clocks in at 48 seconds...the 720 at 35.

But then when I run hyper pi, where you can select the number of cores, setting both at 4 cores, and both calculating to 2M digits...the x4 comes in at 53.726 seconds for the slowest core, the 720 has a slowest core of 1 minute, 4 seconds.

ALSO when I run super or hyper pi, the clock speed on the 720 actually drops. I have it set on Performance, and it's idling at 2.7ghz....I run either Pi program and it DROPS to 2.1 about.


So I guess I have 2 choices; Performance and no underclocking, or default HP and 90% max performance and regular underclocking. Of course I could just jump between the two.

 

[MrMatt]

no ideas?

 

[Visaoni]

The i7 has hyperthreading. That is why it beats your x4 when running Super Pi. When you use Hyper Pi to set it to only run on 4 cores, naturally your higher-clocked x4 will beat the i7.

As for the rest of your i7 clockspeed issues, I can't really say. It sounds like they haven't quite got the power profiles to work all that smoothly.