Is Sandra's Mem. Bandwidth reporting accurate?

phaxmohdem

Golden Member
Aug 18, 2004
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I'm trying to get an old idle rig ready to do some video encoding for a film festival I will be hosting in a month or so. (Users will upload their vids, and it will be encoded to flash FLV via ffmpeg, for posting on the festival website) I thought I'd replace it's RAM which was 1GB (2x 512MB) PC2-4200 DDR2 memory with either some 2x512MB Dual channel 667, or 2GB single stick of DDR2 800 (What I have laying around).

However, I decided to benchmark each setup with Sandra 2009's memory bandwidth test to see what the optimal solution was and I get roughly the same result

Dual Chan PC2-4200: ~4.73 GB/s
Dual Chan PC2-5300: ~4.89 GB/s
Sing Chan PC2-6400: ~4.96 GB/s

I checked the BIOS under each config, and it properly reported dual channel and single channel mode & DIMM speeds.

Something is off here, because IIRC The following should be the theoretical max bandwidth for each setup:

Dual 4200: ~ 8.4GB/s
Dual 5300: ~ 10.6GB/s
Sing 6400: ~ 6.4GB/s

System info of note:
Mobo: Intel DQ965GF (Intel Q965 Chipset)
CPU: Core 2 Duo E6400 @ stock (2.13GHz)

Help?