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Read the Safety Procedures. Very Important!!!

There are four types of memory

  1. SIMMs (single in-line memory modules) have 72 pins. A SIMM can use either FPM (fast page mode) or EDO (extended data output) technology. A SIMM measures 4 1/2 inches long and consists of 72 pins along the bottom of the module (36 on each side). FPM and EDO speeds are often presented in nanoseconds. The lower the number, the faster the RAM.

  2. DIMMs (dual in-line memory modules) may have either 168 pins or 184 pins. Has one notches cut out along the pins

  3. RIMMs (Rambus dynamic RAM) has two notches cut out along the pins. May have 184 pins.

There is many different types of memory available for computers. You have to check the specifications of your system to know which type your system takes.  Below is a short list of the different memory.

There is different types of memory. Some memory only require one stick of memory to be added at one time. This is usually SDRAM. You do not have to worry about the memory matching. Another words, you have 4 memory slots and only one is being used. You have a 128 memory stick in the first slot. You decide to upgrade your memory with a 256 stick. You can do that. Just put the stick in any one of the empty slots. Now you will have 384 megs of memory.

There is some memory that requires you to install the memory in pairs. If you have four memory slots, you may be required to have a card in each slot (some may be dummy cards to fill the slot). If you have two 128 meg sticks of memory and two blank cards and you want to add another 256 megs to the system, you will have to buy two 128 meg sticks and put them where the blank cards are.

Memory limits

Each motherboard has its limits on how much memory it can handle. Some older motherboards can only go up to 512 megs of ram to 1 gig of memory. Some of the newer systems can go up to 4 gigs of memory for a 32 bit system to 16 gigs of memory for a 64 bit system.

On some 32 bit systems, you can install up to 4 gigs of memory but only 3 gigs will show in settings. That is because the system reserves the last gig for memory and other uses.

Installation of memory

Memory install - How to install memory

Installing memory is a vary simple task (unless it is located in an awkward place inside the system).

Troubleshooting memory issues

 If you buy memory for a system, make sure the place you purchase the memory from has a refund policy. The memory might say that it is compatible with your system and when you install it, it won't come on. This doesn't mean the memory is bad or a hardware issue. It can be a compatibility issue. If that is the case you will have to try a different brand.

If you are having an issue that you think is the memory. Here is some things you can try.

Depending on the type of memory you have, you can try the memory in a different slot. Some types of memory, such as RDRAM requires two sticks and won't POST without both in.

RDRAM requires all memory slots to be occupied and because of this, you can't try different slots during troubleshooting. If you have four memory slots then all four will have to have either memory or have a continuity card in it. Both channels have to match in size. If you have two slots then you have one channel. If you have four slots you have two channels. If you have a 128 meg chip in slot one then you have to have 128 megs in slot two. On slot three and slot four you can have continuity chips or additional memory.

SDRAM doesn't require all slots to be used so you can try different slots. If you have two sticks of memory then you can try system with one stick at a time.

You can try that memory in another system that uses that type of memory.

Check the beep code and lights when the memory is in and when it is out. Each computer is different on the diagnostic lights and beeps so you will have to check with the manufacturer for information on the diagnostic indicators.

Click here to download memory diagnostics

Additional information

For information on memory, click on the links below