AMD 32494A gx screentear free download

File name 32494A_gx_screentear.pdf

AMD Engineering - Internal Use Only - October 4, 2004 9:55 am AMD GeodeTM GX Processors Intermittent Screen Tearing Issue Resolution 1.0 Scope 2.0 Discussion This document provides a programming resolution for an During testing of the Geode GX processors, some devices Intermittent graphics issue observed with the AMD exhibited a tearing in the rendered display. The pro- GeodeTM GX processor (i.e., Geode GX [email protected] pro- grammed value in the RAM Control MSR (MSR Address cessor*, Geode GX [email protected] processor*, and Geode GX 80002012h) bits [26:24] and [18:16] were found to be the [email protected] processor*). cause of this issue. (See Table 2-1 for bit descriptions.) The default BIOS value of 4h (100b) is incorrect and needs to be changed to 6h (110b). The full value of this register should be changed in the BIOS from 04040202h to 06060202h. Additional testing with the new value corrected the observed problem. Table 2-1. MSR_RAM_CTL Bit Descriptions Bit Name Description 63:27 RSVD Reserved. Write as read. 26:24 DFIFO_CTL1 DFIFO RAM 1 Delay Control. This bit determines the precharge delay for the DFIFO1 DFIFO0, CFIFO, or DV] RAM cell. (Recommended setting: 110.) 23:19 RSVD Reserved. Write as read. 18:16 DFIFO_CTL0 DFIFO RAM 0 Delay Control. This bit determines the precharge delay for the DFIFO0 RAM cell. (Recommended setting: 110.) 15:11 RSVD Reserved. Write as read. 10:8 CFIFO_CTL CFIFO RAM Delay Control. This bit determines the precharge delay for the CFIFO RAM cell. 7:3 RSVD Reserved. Write as read. 2:0 DV_RAM_CTL DV RAM Delay Control. This bit determines the precharge delay for the DV RAM cell. *The AMD Geode GX [email protected] processor operates at 400 MHz, the AMD Geode GX [email protected] operates at 366 MHz, and the AMD Geode GX [email protected] processor operates at 333 MHz. Model numbers reflect performance as described here: http://www.amd.com/connectivitysolutions/geodegxbenchmark. 32494A - October 2004 - Confidential 1