This chapter tells you how to install and remove DIMMs.
The Silicon Graphics 320 visual workstation contains twelve DIMM slots split into two 6-slot groups, A and B, as shown in Figure 3-1.
The minimum amount of memory installed is 128 MB, filling slot group A with single-sided DIMMs. As long as you install DIMMs in groups of six (filling slot group A first, then slot group B), you can upgrade by replacing the current DIMMs with a higher capacity and/or by adding DIMMs of the same or higher capacity. The maximum configuration is 1 GB of memory, filling both slot groups with 512 MB double-sided stacked DIMMs.
Table 3-1 displays the possible memory configurations. For optimal performance, if you are installing different capacity DIMMs in slot group A than in slot group B, install the higher-capacity DIMMs in slot group A. See “Installing DIMMs” for instructions on how to install DIMMs.
 | Caution: Only install DIMMs that are qualified for the Silicon Graphics 320 visual workstation. |
Table 3-1. Possible Memory Configurations
Total Memory | Slot Group A | Slot Group B |
|---|---|---|
128 MB | 128 MB single-sided | Empty |
256 MB | 256 MB double-sided | Empty |
| 128 MB single-sided | 128 MB single-sided |
384 MB | 256 MB double-sided | 128 MB single-sided |
512 MB | 512 MB double-sided stacked | Empty |
| 256 MB double-sided | 256 MB double-sided |
640 MB | 512 MB double-sided stacked | 128 MB single-sided |
768 MB | 512 MB double-sided stacked | 256 MB double-sided |
1024 MB (1 GB) | 512 MB double-sided stacked | 512 MB double-sided stacked |
Read “About Memory” first before installing DIMMs.
Shut down the system and turn off the power. For detailed instructions, see “Shutting Down the System”.
Unplug the power cord from the back of the system.
Remove the side cover. For detailed instructions, see “Removing the Side Cover”.
Touch a metal part of the chassis with your hand to discharge any static you might be carrying.
Identify the DIMM slot groups, as shown in Figure 3-2. The slot groups—A and B—are split across three vertical rows, with two slots in each row.
Place one hand on top of the workstation to stabilize it while you install the DIMMs, as shown in Figure 3-3.
Install DIMMs in groups of six, whether you are installing six or twelve DIMMs. Install from left to right, two DIMMs in each row, filling slot group A first, then slot group B. Do not mix different capacity DIMMs in the same slot group.
Note: For optimal performance, if you install different capacity DIMMs in slot group A and slot group B, install the higher-capacity DIMMs in slot group A. Position a DIMM so the notch on the longer side faces the rear of the system and the DIMM is at a 90 degree angle to the slot.
Caution: Make sure to install the DIMMs straight on. Installing them at an angle may bend the pins. Carefully push the DIMM into the slot until the latch snaps up into place, as shown in Figure 3-4. If the latch doesn't snap up, you can manually press the latch up to lock it and the DIMM into place.
Replace the side cover. For detailed instructions, see “Replacing the Side Cover”.
Reattach the power cord.
Turn on the system. For detailed instructions, see “Turning On the System”.
Use the Windows NT Diagnostics panel to verify that the system recognizes the DIMMs you installed. To open the panel, select Start > Programs > Administrative Tools > Windows NT Diagnostics. Click the Memory tab. Look at the Total field below Physical Memory to see the total amount of memory recognized by the system.
If the system does not recognize the memory, the DIMMs may be installed incorrectly. Shut down and reopen the system. Then:
Make sure that slot groups contain six of the same capacity DIMMs and that the DIMMs are securely seated in the DIMM slots.
If necessary, read the instructions to remove and reinstall any DIMMs.
Close and reboot the system. If the system still does not recognize the DIMMs, one or more of the DIMMs may be faulty. Contact your support representative.
Shut down the system and turn off the power. For detailed instructions, see “Shutting Down the System”.
Unplug the power cord from the back of the system.
Remove the side cover. For detailed instructions, see “Removing the Side Cover”.
Touch a metal part of the chassis with your hand to discharge any static you might be carrying.
Identify the DIMM slot groups, as shown in Figure 3-5. The slot groups—A and B—are split across three vertical rows, with two slots in each row.
Determine which DIMMs to remove.
If you are replacing lower-capacity DIMMs with higher-capacity DIMMs, remove the lower-capacity DIMMs in groups of six, removing from slot group B first, then slot group A, depending on the number of DIMMs you want to replace.
If you are replacing a faulty DIMM, you need to remove only the faulty DIMM, but you must replace it with another one of equal capacity.
Remove a DIMM by pushing the latch to the left, as shown in Figure 3-6, then pulling the DIMM out of the slot.
Go to step 3 of “Installing DIMMs” for instructions on how to install the replacement DIMMs, replace the side cover, and power on the system.