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Transeau

macrumors 6502a
Original poster
Jan 18, 2005
869
13
Alta Loma, CA
I decided to play a bit this afternoon. I wanted to see the throughput differences with various memory configurations.

Before you post and flame me... I AM NOT TRYING TO SELL YOU ON A SPECIFIC CONFIGURATION. I'm just posting the averaged results to my tests.

Each configuration was tested 10 times and the score was averaged. The tests were done in Single User mode, CLI only. No Networking, GUI, services... nothing.

Config 1: 2x 512MB, Apple OEM
Geekbench Score: 363

Config 2: 4x 512MB, Apple OEM, All DIMMs on Riser 1
Score: 359

Config 3: 4x 512MB, Apple OEM, 2x Riser 1, 2x Riser 2
Score: 418


Config 4: 2x 1GB, Dell OEM
Geekbench Score: 359

Config 5: 4x 1GB, Dell OEM, All DIMMs on Riser 1
Score: 357

Config 6: 4x 1GB, Dell OEM, 2x Riser 1, 2x Riser 2
Score: 421


Config 7: 2x 512MB, Apple OEM, 2x 1GB Dell OEM, 2x Riser 1, 2x Riser 2
Geekbench Score: 347

Config 8: 2x 512MB, Apple OEM, 2x 1GB Dell OEM, All DIMMs on Riser 1
Score: 358

Config 9: 4x 512MB, Apple OEM, 4x 1GB, Dell OEM, 2x2 Riser 1, 2x2 Riser 2
Score: 411

Config 10: 4x 1GB Dell OEM (2x R1, 2X R2), 2x 512MB Apple OEM (2x R1)
Score: 361

My best result came from 4x 1GB DIMMs, configured in DIMM1/2 on each riser. The console in rEFIt confirms this is Quad Channel. The worst result was 2x 1GB on Riser 1 and 2x 512MB on Riser 2. The console confirmed that this is dual channel.

The results were not as dramatic as I expected. I did expect closer to 2x the throughput between Dual and Quad channel mode. There is an improvement of about 18%, and this will show up in memory intense apps. I think the increase would be more if the benchmark used larger blocks of data.
 

Ozy

macrumors regular
Aug 8, 2006
139
4
Goodyear, AZ
Thanks for your tests. I am picking up my Mac Pro today and also getting another 4GB (4x1GB). This will allow 5GB total (2x512MB OEM, 4x1GB OEM). What configuration do you recommend to maintain quad channel performance?

Thx
 
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