LC more fast on a I7 920 than DualXeon 5440?

[cecofuli]

Hi Vlado,

very strange problem. I've a big scene to render. The main WS is a DualXeon Quadcore 5440 2.8 Ghz ( 22.64 Ghz TOT) with 16 GB RAM. The slave is a I7 920 2.6@4.0 (16Ghz + HT) + 12 GB RAM.

(*) If I calculate via BB the LC (IM+LC) only to the slave, it take about 2h. Same time for the other slaves.
(*)If I calculate the LC to the main Workstation (fresh 3ds max restart) it take about 2h 48 min.

LC prepass is 8.

with my old scene test (QMC+QMC), the dualXeon is about 15 min and the I7 19 min. correct result IMO.
I don't have any solution in my mind
I think I must to found the time to format my PC...

[vlado]

Does the xeon have 8 logical cores or 16? If you are rendering a large resolution, turn off the "show calc phase" option for the light cache. Also, as you get more cores, memory speed also becomes very important.

Best regards,
Vlado

[cecofuli]

hi Vlado,

my dualxeon is 2 CPU with 4 phisical CPU. In the task manager I see 8 core and 8 buckets. It's not like the new I7, with 4 Phisical CPU and 8 logical CPU (also 8 buckets in VRay)

Anyway, see this simple scene. LC+LC:

LINK

DualXeon -> VRay estimates 20.40 min to complete the LC in direct mode (no DR, no BB)
I7 920 -> VRay estimates 16.40 sec min to complete the LC

5 min difference it's a huge time!

Now QMC+QMC

DualXeon -> 5.30 min to complete the render (no DR, no BB)
I7 920 @ 4 Ghz -> 4.40 sec to complete the render

3ds max in both PC uses 99%-100& CPU.

Mmm... it's strange. I think I've some problem in my workstation. Both machines have a WinXP64bit. I try to format my Xeon and I post the result. Im my old test the Xeon was always fastest!

[cecofuli]

Ok,

with my surprise, my new nodes i7 920 D0 overclocked to 4.0 Ghz is fast like my good old DualXeon Quadcore 5440 2.83 Ghz only when my Xeon is oveclocked to 3.250 Ghz!
Overwise, the i7 it's better!

I run my old test benchmark with all machine in OC:

Xeon 3.250 Ghz: 15 min 53 sec
I7 4.0Ghz : 15min 26 sec

With the last scene for the LC test:

Xeon 3.250 Ghz: 17 min 38 sec
I7 4.0Ghz : 17min 16 sec

Bye bye