DDR3 Isn't Worth The Money - Yet

An anonymous reader writes "With Intel's motherboard chipsets supporting both DDR2 and DDR3 memory, the question now is whether DDR3 is worth all that extra cash. Trustedreviews has a lengthy article on the topic, and it looks like (for the moment) the answer is no: 'Not to be too gloomy about this, but the bottom line is that it can only be advised to steer clear of DDR3 at present, as in terms of performance, which is what it's all about, it's a waste of money. Even fast DDR2 is, as we have demonstrated clearly, only worthwhile if you are actually overclocking, as it enables you to raise the front-side bus, without your memory causing a bottleneck. DDR3 will of course come into its own as speeds increase still further, enabling even higher front-side bus speeds to be achieved. For now though, DDR2 does its job, just fine.'"

Didn't this happen before?

[xx01dk]

Anyone remember when DDR2 was rolled out and was actually *slower* than the standard of the day, regular DDR? It took about a year IIR for the speed of the newer ramm to catch up and overtake the older ram, and even then it was still pricey. I expect with the current glut in the market of DDR2 that it will take quite a while for DDR3 to be considered a worthy upgrade.

Re:Why do these reviews only focus on one thing?

[julesh]

Every time I see "the need isn't there" or "there's more than enough memory bandwidth" I check their figures, they're only measuring the CPU memory needs.

The reason they're only measuring the CPU memory needs is becase the CPU memory needs dwarf all others.

Max CPU memory access rate (Intel Core 2 @ 1333FSB) = 10.7 GB/s
Max PCIe memory access rate (16 lanes @ 2500MH/z) = 4 GB/s

Total 14.7GB/s over 2 lanes of memory = 7.35GB/s ~= 1800MHz. So, if both your CPU and your I/O devices are running at 100% capacity on a current high end system, you might benefit from DDR3 memory (2GB for £406 from my usual supplier). If, however, you can put up with not using 100% of your CPU capacity when you need to use your I/O capacity (I think most people can, you know) you can get 10.7GB/s with DDR2/667, (2GB for £56 from my usual supplier).

I don't see why the faster memory is worth paying enough extra that I could buy an entire extra computer instead, when I will only use it in the rare case I'm maxing out both I/O bandwidth and CPU bandwidth.