H132199 - ECA001, 8642 SCSI CABLE REPLACEMENT (4X-CDROM) PURPOSE: ------------- Note: This ECA expires July 31, 1997 ------------- PURPOSE: This ECA provides two SCSI cables to replace the existing single SCSI cable shipped in a limited number of Server 720 (8642) systems. The new cables eliminate a potential cause of intermittent Read Errors and General Failures when reading from a 4X CDROM. FEATURES: Type, Machines Affected Model, With and/or Feature/Device B/M to be Service System Stage B/M Description Installed Hours Hours 8642 B/M0000000 MODELS 0Z0, 1Z0, 2ZS, B/M0000000 00.5 00.3 AND 4ZS, MFG. BEFORE 12/12/95. (MFG DATE: 512) PHYSICAL CHECK: Affected systems are 8642 models 0Z0, 1Z0, 2ZS, and, 4ZS manufactured in 1995, utilizing a SINGLE multi-connector SCSI cable. Current production systems utilize the new TWO-CABLE SCSI attachment design, and are not affected. Check the system to determine the cabling method installed according to the following diagrams. 1. SINGLE CABLE METHOD: The CD-ROM is attached between the RAID controller or SCSI adapter and the DASD backplane, as follows: o----------------------o----o---------o--------o o ______|______ | | ___|___ _|____|_ |RAID ADAPT.| Extra "drops" |CD-ROM |DASD | | or | (connectors) | | |BACK- | |SCSI CONTR.| for additional | | |PLANE | |Channel A__| SCSI devices |BAY A1 |BANK C| This configuration includes: o Cable FRU P/N 06H6661 (RAID Array Systems) - OR - o Cable FRU P/N 06H6675 (Non-RAID Array Systems) 2. TWO CABLE METHOD: The DASD BACKPLANE is attached between the RAID controller or SCSI adapter and the CD-ROM, as follows: o-------------o o--------o-------------o----o--o Term. ______|______ _|____|_ ___|___ | | |SCSI ADAPTER |DASD | |CD-ROM| Extra "drops" | or | |BACK- | | | (connectors) |RAID CONTR.| |PLANE | | | for additional |Channel A__| |BANK C| |BAY A1| SCSI devices This configuration requires: o Cable FRU P/N06H3751 (All systems). - AND - o Cable FRU P/N82G3613 (RAID Array Systems) -or- o Cable FRU P/N06H6876 (Non-RAID Array Systems) If the Server 720 has the SINGLE SCSI cable, with the CD-ROM attached between the SCSI controller (or the RAID adapter) and the DASD Backplane, this ECA is applicable. PREREQUISITES: NONE COMPANION: NONE CONCURRENT: NONE DETAIL: Early production of the Server 720 contained a single multi-drop SCSI cable, where the CDROM drive is connected between the HDD Backplane and the SCSI adapter. Some of these systems, with 4X CD-ROM drives installed, have experienced intermittent "General Failures" or "Read Errors" during CD read operations. These failures may occur during applications or diagnostics. The frequency of failure may change with removal or addition of hardfiles. While no failures have been observed on systems with the 2X CDROM drive, this situation is not a fault of the 4X CDROM drive or any other specific SCSI device. Changing the cabling from the single cable method to the two cable method resolves the problem for all devices. Order one of FRU P/N06H3751 and either FRU P/N82G3613 (Array) or P/N06H6876 (Non-Array) using normal parts ordering procedures. The RAID Controller or SCSI Adapter to Backplane cable will attach to the backplane next to the power connector. Cable FRU P/N06H3751 (Backplane-CDROM-Terminator Cable) will connect from the second connector (on the opposite side of the backplane) to the CDROM drive and will contain termination. FRU Number Description ----------- ------------------------------- 82G3613 RAID Controller to Backplane cable for Array Systems 06H6876 SCSI Card to Backplane Cable for Non-Array Systems 06H3751 Bottom of Backplane to CDROM Terminator Cable (All Systems) NOTES: After December 12, 1995, all Server 720 systems have been manufactured using the "Two SCSI Cable" method. A small number of systems were manufactured with 4X CDROM drives Only the FRU Part numbers listed above (82G3613, 06H6876 and 06H3751) are are valid to use and eligible for reimbursement under this ECA. Use Service Code 33, Other office worked 990, and ECA001 to record parts and labor. This ECA expires July 31, 1997. November 19, 1996