Memory Primer- Giordan on Graphics | 4
As in buying a car or making an investment, when buying memory you really
want your vendor to know more than you do. Asking the following questions
will not give you a whole lot of information to make your final purchase
decision on, but it will weed out the companies that you should avoid. If
a potential vendor cant answer these questions satisfactorily, then
you should stay away from them. These questions set a bare minimum criterion
for product quality as far as memory is concerned.
Is It Composite or Non-Composite?
These terms are getting a little old at this point, but since they are still being tossed about, you should be aware of the distinction between the two. Composite modules appeared on the scene while Apple was transitioning beyond the standard 8MB modules, to the 16MB and 32MB varieties. Some memory vendors were trying to squeeze lots of 4Mb chips onto the board to make up a higher capacity module. Doing this created what the industry called a composite module. Composite modules were problematic in that it didnt conduct heat very well, as well as the fact that the modules were not very sound from an engineering level due to the way that so many chips were squeezed onto one board.
Non-Composite modules are the preferred choice, in that they use 16Mb chips,
which avoid the associated composite problems. If you are buying modules
smaller than 8MB, you do not have to worry about composite modules. If you
buy modules that are 16MB or 32MB, you should simply count the chips on
the board. If there are only 6-8 chips per side, then youre OK. If
there are 16-24 chips on each side, then it is composite, and you should
send it back if you can.
What is the Refresh Rate?
The refresh rate of a module tells you how fast it is. This directly impacts not only the performance of your system, but it also determines whether or not the module will even work in your system. Therefore, you should know the required refresh rate for your system.
What Is The Board Thickness
Memory boards come in either two layer or four layer thicknesses. This means that the four layer have twice as many layers of plastic used in their construction. The importance of using four layer boards revolves around the issue of heat. As memory is used in your system, the RAM gets very hot. As a module heats up, the two-layer boards can warp and bend. In addition, the constant heat up and cool down caused when a machine is turned off and on actually expands and contracts the module. Over time, the two layer modules can break down, as their traces become worn, or the boards themselves begin to crack.
What is The Warranty and Guarantee?
You want to find a company that offers you a 30 day return policy, as well as a lifetime warranty. This means that you can install the product and make sure that it works within the first 30 days. While even the best companies have products damaged during shipping, if a company cant get their stuff to work in 30 days, then forget about it. You want to send the product back at this point, and they should refund your money.
The warranty simply says that if the memory fails at any point, you are eligible to return the product for replacement. If its well built, memory seldom fails, so this is not a big risk on the memory vendors part. Besides, the way technology keeps changing, a lifetime warranty really amounts to a 4-6 year warranty, even on the most advanced machines. Beyond that amount of time, your system will end up in a museum anyway.
fin
Produced by Daniel Giordan
All Rights Reserved. Legal Notices.
URL: https://www.webreference.com/graphics/column14/
Created: May 17, 1999
Revised: May 17, 1999