The 512mb modules are single rank modules. Buy from Crucial or Ramjet and rest easy. When you add memory to your ThinkPad, you may have a choice between single rank and dual rank modules, often at the same price. Even more important, choose dual channel two modules over single channel one module for best performance, a difference of up to 20% in certain appliations. Sorry I had to spank the monkey a little bit, but I guess some poeple do their best work when their pissed off. A single-sided module is always single-rank.
I sometimes mention that the module is for 1. Think of it as each rank draining the address bus a bit. But high-capacity single-rank modules are very expensive. The ranks mean if it has chips on one side of the stick or both sides. Identify the pins, scrape labels off, get out a magnifying glass, etc.
For example, the controller can send write data to one rank while it awaits read data previously selected from another rank. The reason is because of the addressing scheme, which can extend the pages across ranks thereby making the pages effectively larger and therefore more page-hit cycles. Controlling interleaved accesses like so is done by the memory controller. You may have gotten a bad module. The poster was replying to someone else's question, but it seems to answer mine too. Replace the old one and you should be fine.
Wide selection, great prices, unmatched service is what we do since 1998! I'm looking on a 30pin stick and just can't find those pins. My last question for the moment is how to do this if buying online or how to talk a store clerk into lettin' me do all this? This could lead to confusion and technical issues. That applies only to quad rank or higher -- single and dual rank usually have the same timings -- and thus isn't relevant to laptops. The 840 support up to 8gb 4x2gb. Here are a couple of replies I got from John Mayer from Ramjet. A memory Rank is, simply put, a block or area of data that is created using some, or all, of the memory chips on a module.
Since I can not proof why this should be the best way to set it up, I suggest you try a benchmark program for memory throughput. You have absolutely no idea of what you're talking about so don't think for one second we're not gonna call you on it. Four ranks one quad-rank, two dual-rank or four single-rank will demand to lower memory speed on one step making total productivity about the same as with the only single-rank module. . Same as with memory banking, the more modules ranks you install, the slower memory speed is allowed. Otherwise, you might try this; Pins 33 and 45 on the board are used by double-sided memory, and can sometimes be an indicator as to whether a given module is single or double-sided. The concept of memory Rank applies to all memory module form factors, though in general it tends to matter primarily on server platforms, due to the larger amounts of memory they manage.
I have read the articles you forwarded to John Mayer, and yes, definitely the dual rank is preferable in the Mac Pro. This tradeoff between memory cost and capacity is important to consider when purchasing memory modules for Intel Lindenhurst-based servers. Net is the opinions of its users. The reason is because of the addressing scheme, which can extend the pages across ranks thereby making the pages effectively larger and therefore more page-hit cycles. For example, a server with four memory slots may be limited to a total of eight Ranks.
The replacements that I was sent were rank 1 were as the ones they were replacing were labled rank 2. Ars may earn compensation on sales from links on this site. While the write data is consumed from the data bus, the other rank could perform read-related operations such as the activation of a row or internal transfer of the data to the output drivers. Generally one group is located on each physical surface of the stick, but not always. Additional information on ranking and the systems it typically applies to can be found. This means that motherboards must physically be designed to support dual-rank memory modules. Not to confuse the issue more, but another term applied to Mac Pro dimms is dual channel.
Is the term Dual Rank being used erroneously by some of the vendors and review sites out there or is Dual Rank really what I want contrary to what John from Ramjet. The drawback with higher Ranked modules is that servers sometimes have a limit on how many Ranks they can address. Actually I found this info on another site. Please check your user manual Below are memory modules currently available from integral memory. A single ranked dimm only has memory chips on one side of the dimm.