Wow, i7 920 twice faster Q6600

shurcooL

[H]ard|Gawd
Joined
Oct 12, 2007
Messages
1,125
I've recently had a chance to compare my Core 2 Quad Q6600 2.4 GHz (4 cores, 4 threads) with DDR2-800 RAM against a Core i7 920 2.66 GHz (4 cores, 8 threads) with DDR3-1067 RAM.

I was surprised by the results.

In single-threaded CPU-bound tasks (e.g. SuperPiMod 1.5), the i7 920 was about 65% faster (51 seconds vs. 31 seconds).

In multithreaded CPU-bound tasks (e.g. wPrime 2.03), the i7 920 was almost twice as fast (20 seconds vs. 10 seconds).

I've confirmed it in a real world test case by taking a somewhat large C++ project (612 source files) and recompiling it from scratch in Visual Studio 2010. The project was stored on a RAM disk, so HDD was not a factor.

It consistently took 30 seconds to fully compile on i7 920, and 60 seconds on the Q6600.

Is this normal? I thought the Core i7s were only 20-30% faster clock-per-clock than Core 2 CPUs. In any case, I'm impressed. I wonder how a 2500K would stack up.
 
Is this normal? I thought the Core i7s were only 20-30% faster clock-per-clock than Core 2 CPUs

They are 20% to 30% faster clock per clock. However you have a faster clock with the i7 and 8 threads instead of 4. You also have faster and higher bandwidth ram. That all adds up.

I wonder how a 2500K would stack up.

Not as clear cut in multithreaded tests since you are giving up 4 threads. Are you going to overclock the i5? I ask since it appears you did not overclock either of the other two machines.
 
Last edited:
They are 20% to 30% faster clock per clock. However you have a faster clock with the i7 and 8 threads instead of 4. You also have faster and higher bandwidth ram. That all adds up.
Yeah. Surprisingly.

Not as clear cut in multithreaded tests since you are giving up 4 threads. Are you going to overclock the i5? I ask since it appears you did not overclock either of the other two machines.
Sorry, I meant 2600K. I didn't realize there was such a big difference between the two. I thought 26 was with an unlocked multiplier for easier OCing and 25 without, not much else.
 
Last edited:
Yeah. Surprisingly.


Sorry, I meant 2600K. I didn't realize there was such a big difference between the two. I thought 26 was with an unlocked multiplier for easier OCing and 25 without, not much else.

It's the letter "K" that identifies processors with unlocked multi. So both the 2500k and 2600k are unlocked. 2600k has hyperthreading while 2500k does not.
 
The q6600 was a LOT of CPU for the buck.

The I7-920 is still a LOT of CPU for the buck.

My I7-920 is o/ced to 4.0ghz. I played a few hours of metro 2033 with dx11 and highest settings on my GTX560 ti card and looked at the CPU chart. <= 50% CPU usage. There is a LOT of life left on these 3 year old I7-920's still!
 
Sorry, I meant 2600K. I didn't realize there was such a big difference between the two. I thought 26 was with an unlocked multiplier for easier OCing and 25 without, not much else.

Okay now the 8 threaded 2600K has 10 to 15% improvement clock for clock over the first generation i7, plus 740 extra Mhz over the 2.66 Ghz i7 920 + the improved Turbo or the greatly increased overclocking potential of the i7 2600K. I would expect the i7 2600K overclocked to be 3 to 4 times as fast as the 2.4GHz Q6600 at stock in the 8 threaded compile from a ram disk example that you gave in your first post.
 
Sorry, I meant 2600K. I didn't realize there was such a big difference between the two. I thought 26 was with an unlocked multiplier for easier OCing and 25 without, not much else..
The big difference was 4 threads versus 8 threads in your highly threaded example.
 
Okay now the 8 threaded 2600K has 10 to 15% improvement clock for clock over the first generation i7, plus 740 extra Mhz over the 2.66 Ghz i7 920 + the improved Turbo or the greatly increased overclocking potential of the i7 2600K. I would expect the i7 2600K overclocked to be 3 to 4 times as fast as the 2.4GHz Q6600 at stock in the 8 threaded compile from a ram disk example that you gave in your first post.
Nice. So like 15 seconds then. Awesome technology.

I'll probably wait until Ivy Bridge and get something new then. It'll be an awesome improvement.
 
Back
Top