Memory - Published on Friday, 21 March 2003 17:19 Written by Anton Karmehed
Corsair's LL-suffix alludes to the RAM-modules memory timings, something we often write about here at Nordichardware.
On page 2 we went through the basics of memory timings, and the conclusion was “lower memory timings equals’ better performance”.
LL is the abbreviation of Low Latency and means lower memory timings, lower latency.
Since many users don't feel comfortable in poking with BIOS and manually change memory timings, Corsair have introduced the LL-marking.
To get the concept of Low Latency working Corsair has done two main things.
1. Optimized the memory modules for usage with low memory timings.
2. Made sure that the motherboards understand that the memory is optimized for usage with low memory timings.
How the first goal is reached, we don't know for sure. Probably Corsair has made sure the development of TWINX modules has been focused on optimizing them for low timings.
The other thing that Corsair changed on their LL-modules is their SPD chip.
SPD (Serial Presence Detect) is the name of the EEPROM chip (electrically erasable programmable read-only memory) that is integrated on all SDRAM modules.
Without this chip it's impossible to even start the computer which of course is something you would want to avoid.
The SPD chip is programmed by the manufacturer and contains information that the BIOS (Basic Input Output System) uses to adjust size, speed, voltage and timings for the memory module.
Most modules have relatively slow memory timings programmed in the SPD chip, to secure the systems stability. This on the other hand forces the user to manually change the settings in BIOS to get optimal performance, and this is something far from everyone is prepared to do.
Even if it doesn't harm the modules physically if you enter values that are too low, the system may refuse to boot, which for the inexperienced user can be bad enough.
The simple thing Corsair have done is that the SPD chip is programmed with low memory timings from the beginning, which mean that even the inexperienced user get optimized performance, without even touching the BIOS.
Default values on Corsair TWINX512-3200LL is 6-2-2-2 all the way up to DDR400-speeds.
We tested this function practically by letting BIOS automatically enter the timing values for Corsair XMS3500C2 and Corsair TWIN512-3200LL, on our test motherboard EpoX 8RDA+.
Clearly there are big differences on the modules timings, also take in mind that Corsair XMS3500C2 actually is one of the best performing memory modules on the market at this point.
How big difference this does to the performance is something we're going to take a closer look at later on. We will also figure out if Corsairs LL-marking only is for the novices, or even something for the real picky users.
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