Sign in with
Sign up | Sign in
Your question

QPI speed on different Core i7 models.

Last response: in CPUs
Share
August 2, 2010 11:52:38 AM

The QPI speed on all of the Core i7 models is 4.8 GT/s with the exception of the extreme editions. The extreme edition Core i7's have 6.4 GT/s QPI. Why is this?

Is there any way of increasing the QPI frequency in the BIOS?

Would a Core i7 975 EE be faster than a Core i7 930 if they were both clocked exactly identically, on identical systems?

More about : qpi speed core models

a b à CPUs
August 2, 2010 12:06:59 PM

Probably higher just to make it actually seem as if it's different and worth getting somewhat. I believe raising the BCLK on the Core i7s also raise the QPI, and by changing the QPI multiplier you can change it. Note that the Core i7 800s have a QPI link speed of 2.5 GT/s.

I'm pretty sure that the extra speed doesn't help, someone correct me if I'm wrong but all it does is transfer information from motherboard to other PC components, and the majority of the time there isn't that much data to transfer which is the reason why higher CPU clock speeds are far more important, and QPI frequency doesn't affect the CPU speed that much. (The Core i7 860 has a higher Turbo Boost than the Core i7 920, and thus beats it in most single threaded applications, if not all... yet the i7 920 has nearly double the QPI frequency)

To answer your question based on the logic, yes, but slightly, and depends on your hardware configuration.
m
0
l
a b à CPUs
August 2, 2010 12:27:54 PM

QPI is the super fast(about twice as fast as DMI) connection between the CPU and MB. However, LGA1156(DMI) i7 is actually faster than the LGA1366(QPI) ones at the same frequency in non-memory intensive apps (i.e. excluding video encoding...etc) since both PCIE controller and North Bridge are integrated into LGA1156. Thus, I would recommend 860 instead if you don't benefit from the extra memory (i.e. usually LGA1366/6GB v.s. LGA1156/4GB). BTW, Sandy Bridge would be great if NB/PCIE controller are integrated into it with QPI.
m
0
l
a b à CPUs
August 2, 2010 12:32:18 PM

ambam said:
The QPI speed on all of the Core i7 models is 4.8 GT/s with the exception of the extreme editions. The extreme edition Core i7's have 6.4 GT/s QPI. Why is this?

Is there any way of increasing the QPI frequency in the BIOS?

Would a Core i7 975 EE be faster than a Core i7 930 if they were both clocked exactly identically, on identical systems?

I don't think so. However, you can always "OC" QPI speed by raising QPI multiplier of 930 if desired.
m
0
l
!