HP Model 744 HP Model 744 Owner's Guide - Page 70

Typical Installation in a VME Card Cage Configuring the VME Card Cage 2 To determine the maximum current usage of the Model 744 memory cards, either use Figure 3-1 and Table 3-2 (for Model 744/132L) or Table 3-3 (for Model 744/165L). You must work with the worst case power draw to correctly determine power usage. Determine worst case power draw by examining active memory bank configurations, using the following steps: a Examine your memory card configuration, noting which size card is in each memory slot. b The worst case active memory bank configuration depends on the slot position of the memory cards, and the size of the cards. The 32MB memory card has two banks per card, and the 16, 64, and 128MB cards each have only one memory bank per card. • When 32MB cards are used as a pair in memory slots 2 and 3 they can use three memory banks concurrently. • When used as a pair in slots 0, 1, or 2, the 32MB cards can have two active memory banks. • The 16, 64, and 128MB cards each have only one memory bank that is active at any one time. The worst case power draw would be if your system had 2 32MB cards in slots 2 and 3 (these banks would be considered active, all other memory cards/banks would be considered inactive). If you do not have that configuration, the next worst case would be a 64MB card in any slot (all other memory cards in the system would be inactive), followed by 2 32MB cards in slots 0, 1, or 2 (all other memory cards in the system would be inactive), followed by a 16MB card in any slot (all other memory cards in the system would be inactive). c Inactive memory banks are those banks on cards in your configuration in addition to the worst case active memory banks, and must also be added to the calculation. d Fill in the information in Table 3-2 or Table 3-3. 3-4