DDR2 vs DDR3: The Battle of Latency vs. Bandwidth - Asus P5K3 Deluxe WiFi & Corsair TWIN3X2048-1333C9DHX Review - PAGE 1

Today we are going to take a look at a new DDR3 motherboard, and a new DDR3 memory module - but before we do that, let's take a quick look at how we got here...

In the beginning, there was static ram - and it was good - however each bit of memory needed six transistors, limiting how many bits could be implemented on a chip, and they thus dynamic ram was invented. Dynamic ram only needed a single transistor and a single capacitor for each bit,  so it could be a lot denser - packing around three times as many bits per square millimeter as static ram.

Dynamic ram then lead to double data rate dynamic ram. Eventually, DDR evolved to DDR2 - then war broke out... fought on two great battlefields. They were upon the fields of Latency and the oceans of Bandwidth.

Initially, DDR had vastly better latency than DDR2, and was not very far behind on bandwidth. It looked like DDR2 might lose the war.

But wait.

As processes were improved, DDR2 was able to reach greater heights in the all mighty MegaHertz ranks. DDR2-667's were able to hold their own against DDR-400. DDR2-800 started to take the lead... and then DDR2 low latency memories started to appear. The once strong DDR began to falter.

Eventually, the DDR camp had to admit defeat... DDR2-1066 5-5-5-15 was too much for it to compete against... and with DDR2-1111 low latency memories coming in later.. well, the less said, the better. And there was peace for a while, as DDR2 dominated.

Now, the reign of DDR2 has a challenger. DDR3 -  and we get a stong sense of Deja Vu (or is our memory playing tricks on us again?). 

And that brings us to today. What we have now is DDR3 boasting higher Megahertz ratings than DDR2 - but at the expense of increased latency.  The familiar struggle continues, and many of you will have noticed in my past articles the importance of balancing latency and higher frequencies to achieve overall maximum performance.  Let's see how early DDR3 modules manage this balance.

The best available JEDEC standard DDR3 modules are DDR3-1333 at 9-9-9-24 timings... a far cry from the best low latency DDR2-1111 4-4-4-12 timings - not to mention the DDR2-1250 5-5-5-15 modules almost matching DDR3 in speeds with still much lower latencies and I think history will repeat itself. The DDR2 camp may currently be laughing at the feeble latency and performance of the low end DDR3-1066 9-9-9-24 modules, but then later realizing that DDR3-1333 may be the point of parity - and that DDR2's doom may well be sealed by DDR3-1600 and above.

Let's see what we can find out about existing modules.

DDR2 and DDR3 are both memory technologies that attempt to provide computers with high bandwidth memory.

As manufacturers have pushed DDR2 well beyond its originally intended PC2-6400 (800MHz effective data rate) and since there does not appear to be any letup in the "need for speed", memory manufacturers have started making DDR3 devices in order to far surpass the bandwidth they can easily get from DDR2 devices - and reduce power consumption and heat generation at the same time.

As DDR2 frequencies went up, so did the voltages required to perform at the higher data rates - and of course this caused ever more heat to be generated. Heatspreaders became heat sinks... then came optional fans... and some manufacturers went so far as to mount water blocks on the DIMM's!

Now that DDR3's run at lower voltages - they generate less heat.

In our lab we are fortunate enough to have some excellent DDR2 memory devices, and to make the test even more interesting, we have DDR2 and DDR3 versions of the (essentially) same Asus P5K / P5K3 Deluxe WiFi AP motherboard. In our recent review of the Asus P5K Deluxe WiFi, we found it to be an excellent performer - and the P35 chipset appears to provide good performance for enthusiast boards.

But enough of that for now... let's look at the new DDR3 capable Asus P5K3 Deluxe WiFi, and the Corsair TWIN3X-2048 1333C9DHX modules!