Parallel Processing, Part 2: RAM and HDD

By Patrick Schmid
published

Synthetic Benchmarks

Not even PCMark 05’s memory benchmark seems to be impressed by the missing dual channel mode.

We found the same results in the overall score.

Sandra 2008 does shows a distinction between single channel and dual channel DDR2-800 operation: 5.7 GB/s versus 6.4 GB/s is a clear difference, but far from the theoretical 50% gap.

Application Benchmarks

The two application benchmarks 3DSmax and WinRAR don’t suffer much if dual channel memory mode is disabled. In particular, we did not expect WinRAR to remain at roughly the same performance when run in single channel memory mode.

Patrick Schmid
7 Comments Comment from the forums
  • perzy
    This is a great article!
    Reply
  • (Firt of all: Excuse my poor English... )
    mmm yours memory tests don't convince me. You should run, for example, Winrar AND Lame IN PARALLEL/SIMULTANEOUS (i.e multitasking), otherwise, caches don't are flushed (and it's when dual channel really is important). Note that it's not a superflous situation; under normal use a system commonly have several huge memory applications run concurrently (word, browser whith a lot of tabs open, anti-virus, etc. )
    el_bot
    Reply
  • hellwig
    I doubt anyone from Tom's will see this comment on such an old article, but it would have been interesting to see Single-vs.-Dual channel memory using an AMD processor. Since Tom's like Intel, the new Core i7's would also be beneficial. The point is, the article acknowledges the Core 2's have a tremendous amount of L2 cache to combat FSB (and consequently Memory) latencies. How is the comparison with an AMD or nwe Core i7 where there is NO FSB and the L2 Cache is significantly reduce? I would imagine this is where dual/tripple-channel shows is mustard. I hope we see a single vs. dual vs. triple channel comparison soon.
    Reply
  • meodowla
    Won't it be different when using a AMD processor with Memory Controller inside CPU.
    Reply
  • junghm69
    My Windows Experience Index 3D gaming graphics score goes up from 3.8 to 5.1 when I switch from dual channel to single channel. This makes absolutely no sense. I thought dual channel was supposed to be better than single channel. Can anyone explain this?

    I seriously doubt that this score is accurate. I am using the built in graphics controller on the motherboard which is an AMD 760G chipset (ATI HD 3000 or 3200 I think). I've used Radeon HD 5450 video cards on similar systems and they give me a score of 5.4. How can a built in graphics controller give me a 5.1?

    AMD Athlon II X3 435 Rana (2.9 ghz)
    Asus M4A78LT-M motherboard
    4 GB G.Skill DDR3-1333 (2x2GB) F3-10600CL9D-4GBNT CL9-9-9-24 1.5V
    Windows 7 Ultimate 64-bit
    Reply
  • junghm69
    because if you used 2 different memory chips both will run at the speed of the lowest memory chip when you activate dual channel in your motherboard
    Reply
  • Caramac
    That earlier article on Processors doesn't work, so I'll add this:
    Intel HyperThreading - leading to the "H T" on the 'Intel Inside' sticker of computers with that 875p chipset and a single core Pentium 4 processor.
    It equals simulated dual core tech.
    Some Core processors also have HT.
    http://www.tomshardware.com/forum/340555-28-intel-hyperthreading-helpful
    Reply