DRAM, Chip Set, Personal Computer, Printed Circuit Board, Assembly, Commodity DRAM, Urgent Need for Cheap, Readily Used DRAM, New Era, Overcoming the Compatibility Crisis, Expansion of Design Margins, Dealing with Problems, It is becoming difficult to use DRAM. Although it isn't difficult to just use a specific product from a specific maker, things become very difficult when a PC or home electronic appliance carries DRAM from multiple DRAM makers. This is because true compatibility has been lost even though various company's product specifications appear the same. The major reason for this is that, accompanying the speed up in operating cycles, in-use design margins have shrunk. New interfaces to solve the timing problem, as well as installation of a memory driver for each SIMM module to decrease waveform distortion, have been proposed as countermeasures. However there can be no complete solution when the command error problem is also considered. It is important that DRAM makers have their own countermeasures to completely solve such problems. Some companies have begun burn-intesting and failure analysis. PC developers are now often heard to ask in complaint, Why doesn't it work? This problem results from the inability of the various makers of commodity DRAM to maintain compatibility. Despite DRAM being the same form and type, there are cases of such DRAM operating or not operating upon a given mother board depending upon the DRAM manufacturer (Figure 1). New interfaces to solve the timing problem, as well as addition of a memory driver to the SIMM to decrease waveform distortion, have been proposed as countermeasures. Moreover, DRAM makers have begun to establish specialized departments for burn-in testing and failure analysis. Now Impossible to Speak of Commodity DRAM, In the beginning, DRAM of various manufacturers was mutually compatible. In other words, there was a typical commodity product. Many PC systems were constructed while assuming that such DRAM was mutually compatible. The memory division at NEC anticipates 160% growth (bit-basis) of demand. However, if a specific maker's DRAM is required for operation, the assumptions upon which such a forecast is made are violated. PC systems become inoperable as soon as supply from a given DRAM maker stops. NEC therefore says that it is not possible to speak of commodity DRAM. This kind of compatibility problem has really begun. Trouble is actually occurring when DRAM, from a manufacturer other than that of the original DRAM, is installed on a given motherboard. There are cases in which such DRAM combinations do not operate. DRAM that is sold as the same type does not function the same. Some PC makers are even considering avoiding the latest DRAM if this problem is not solved. This is the environment in which DRAM speed-up is taking place ...  
 

 

 

Return to J-Tech Homepage