Corsair TwinX1024-4000PRO Memory

A Brief Explanation of RAM Timings

This review will not only show you how each of the TwinX kits perform, but it will also show the differences between low latency and high bandwidth RAM. Yes, the kits are of different sizes (512MB vs. 1024MB), but that has less of an impact than you might think, at least when running most benchmarks. It has a much greater impact while gaming, that's for sure! The kits are also designed to run with different timing settings. Before we get started with the test results, let me give a brief explanation of what the different RAM timings are.

Most of the time, you will see the timings for a given RAM listed as a series of numbers, such as 2-3-3-6-1T. The numbers are the settings for CAS Latency, RAS to CAS Delay, RAS Precharge, Active to Precharge, and Command Rate. Sure, lower numbers mean that the RAM should perform better, but why is that? It is because each number represents a delay, in clock cycles, before an action takes place in the RAM.

The Corsair Dual Channel Memory Kits we're looking at today each have a different set of timings. The TwinX512-3200LLPT has timings of 2-3-2-6-1T preprogrammed into its SPD (Serial Presence Detect) chip on the DIMM itself and is designed as PC3200 RAM, which is sometimes referred to as DDR400. While these aren't the tightest timings (smallest numbers) achievable, they're very good for right out of the box. Usually, memory that is made to run with timings this tight does not overclock well. Think of it as skiing downhill with a rocket on your back. Gravity does a pretty good job of getting you going and the rocket adds a nice boost. However, too much boost from the rocket will leave you wrapped around a tree, after you lose control from going too fast and hitting the mogul slope.

The TwinX1024-4000PRO, on the other hand, is preset to run at PC4000 speeds (DDR500) with timings of 3-4-4-8-1T. This is more like putting a rocket on a semi-tractor truck. It won't be terribly maneuverable, but it will go very fast! It also won't be slowed down by little bumps in the road. Of course, if a bridge is out or there's a hairpin turn, you can still crash and burn.

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Select a Page Page 1: Introduction Page 2: A Brief Explanation of RAM Timings Page 3: Testing Methodology Page 4: AIDA32 Test Results Page 5: Sandra 2004 and PCMark04 Pro Page 6: Conclusion