i7, Vista 64 and render speed

ottor wrote on 7/30/2009, 7:44 PM

I have an Core i7 950 system with 6GB RAM, Vista Business 64 SP1 fully updated. Boot array is 4 drives in Raid 0+1 on Intel MB controller, 2 x 1GB Raid 0 arrays on an Adaptec 1430SA controller for video files.

I've installed both Vegas 9a 32bit & 64bit versions on it. Using the same setting in both versions I see a big difference in render times. The 32bit version is 50% faster than the 64bit version when rendering a 1 hour 27 minute mpg2 source file (that has 1 overlaid graphic on it) to another mpg2 output file. The 32bit version does it in 44 minutes, the 64bit version in 65 minutes.

The only difference in prefs between the two versions is the number of threads. 32bit is 4, 64bit is 16. CPU usage is low, maximum of about 35% on any thread. Overall CPU load is about 30%. Changing the number of threads doesn't seem to do anything at all!

On the same machine under XP Pro (32bit) I can render the same project in 42 minutes. Obviously there's something wrong somewhere.

Anyone got any ideas?

Thanks,

Otto

Comments

ritsmer wrote on 7/31/2009, 12:52 AM

A low CPU usage often means that the machine can not read or write the media fast enough to cope with the fast CPU.

There are several threads here about how to distribute the disk load - but the rule-of-thumb is to keep Windows+Program files, Pagefile, input media and output media on 4 different logical or physical drives.

Chethu wrote on 7/31/2009, 9:43 PM

Otto

>>On the same machine under XP Pro (32bit) I can render the same project in 42 minutes.

When you render it under XP do you see CPU usage hitting ~100% ?

-Chethu

srode wrote on 8/1/2009, 4:03 AM

Is this a relatively new build ? Have you done any benchmarking on it to see how it performs? Mem test / Sandra / Atto / IO meter.

ottor wrote on 8/3/2009, 8:53 PM

Attobench results are good, ~230 MB/s to/from the raid drives used for video. Prime95 runs 100% on all threads with no problems. Sandra benchmarks are within the ballpark for the cpu. I'm just running another Mpeg -> Mpeg with overlay, but cropping and converting from NTSC -> PAL and I'm using ~80% on every core which seems better. (This is the Vegas 32bit running on Vista 64).
More as I figure it out.

almach1 wrote on 8/4/2009, 4:47 PM

first time poster here.

I have similar issue but it's between Vegas 8.1 and Vegas 9a(trial). Both are on the same machine running Windows7RC64bit with i7 920cpu.

Vegas 8.1 uses 80+ cpu accross all 8 threads,

Vegas9 uses only 30-40% on all 8 threads.

haven't compared the speed. I will do the same project and see which one renders faster.