Chosen Solution

I believe the blade SSD on my 2017 27-inch Fusion Drive iMac is faulty. The issues I get are extremely slow boot up and shut downs when it freezes up. I ran EtreCheck and it said the SSD was very slow. I was told on the Apple forums the error reports point to the storage for the reason for the kernel panics. I now run macOS on an external spinning HDD and I have to eject the old Macintosh HDD from Finder which definitely does help but still occasionally get the issues above. After seeing the steps on ifixit, I plan on replacing the internal HDD with a 4TB Crucial SSD and remove the blade SSD entirely and not replace it. My question is, will my iMac still function without this blade SSD and instead run entirely on the 4TB Crucial SSD?? Update (05/18/2022) DriveDX output SYSTEM INFORMATION Report Timestamp : 19 May 2022 5:23:00 am AESTReport Timestamp (ISO 8601 format) : 2022-05-19T05:23:00Application Name : DriveDxApplication Version : 1.11.0.730Application SubBuild : 0Application Edition : StandaloneApplication Website : https://binaryfruit.com/drivedxDriveDx Knowledge Base Revision : 101/101Computer Name : iMacHost Name : iMacComputer Model : iMac18,3OS Boot Time : 2022-05-18T22:24:25Time Since Boot : 06h 58m 35sOS Name : macOSOS Version : 10.16.0OS Build : 21E258OS Kernel Version : Darwin 21.4.0SAT SMART Driver Version : N/AATA Command Support Tolerance : verypermissive Number of drives in report : 1 DRIVE 1 OF 1 Last Checked : 19 May 2022 5:13:59 am AESTLast Checked (ISO 8601 format) : 2022-05-19T05:13:59Advanced SMART Status : FAILEDOverall Health Rating : N/A 63.2%Overall Performance Rating : AVERAGE 63.2%Issues found : 6Serial Number : ZA50CDG3WWN Id : 5 000c50 0a2f5c13fVolumes :Device Path : /dev/disk5Total Capacity : 3.0 TB (3,000,592,982,016 Bytes)Model Family : Apple (Seagate-based) HDDsModel : APPLE HDD ST3000DM001Form Factor : 3.5 inchesFirmware Version : AQ03Drive Type : HDD 7200 rpmPower On Time : 21,893 hours (30 months 12 days 5 hours)Power Cycles Count : 43,955Current Power Cycle Time : 7.0 hours DEVICE CAPABILITIES S.M.A.R.T. support enabled : yesDriveDx Active Diagnostic Config : Apple (Seagate-based) HDDs config [hdd.seagate.apple]Sector Logical Size : 512Sector Physical Size : 4096Physical Interconnect : SATALogical Protocol : SATARemovable : noEjectable : noATA Version : ACS-2, ACS-3 T13/2161-D revision 3bSATA Version : SATA 3.1, 6.0 Gb/s (current: 6.0 Gb/s)I/O Path : IOService:/AppleACPIPlatformExpert/PCI0@0/AppleACPIPCI/SATA@17/AppleIntelPchSeriesAHCI/PRT0@0/IOAHCIDevice@0/AppleAHCIDiskDriver/IOAHCIBlockStorageDeviceAttributes Data Structure Revision : 10SMART Command Transport (SCT) flags : 0x10bdSCT Status supported : yesSCT Feature Control supported : yesSCT Data Table supported : yesError logging capabilities : 0x1Self-tests supported : yesOffline Data Collection capabilities : 0x73Offline Data Collection status : 0x0Auto Offline Data Collection flags : 0x0[Known device ]: yes[Drive State Flags ]: 0x44400300[Last State Change Timestamp ]: 2022-05-19T05:14:00[Last State Change Flags ]: 0x44400300[Last State Change Diff Flags ]: 0x1Last Email Report Timestamp : 2022-05-19T05:14:00Last Email Report Reason Flags : 0x44400300Last Email Report State Change Flags : 0x1 CURRENT POWER CYCLE STATISTICS Time since computer startup : 6 hoursData Read : 334,428,672 bytes (334.4 MB)Data Written : 87,269,376 bytes (87.3 MB)Data Read/Write Ratio : 3.83Data Read/hour : 47.9 MB/hourData Write/hour : 12.5 MB/hourOperations (Read) : 14,024Read IOPS : 1Operations (Write) : 1,913Write IOPS : 0Operations Read/Write Ratio : 7Throughput per operation (Read) : 23.8 KB/OpThroughput per operation (Write) : 45.6 KB/OpLatency Time (Read) : 0 nsLatency Time (Write) : 0 nsRetries (Read) : 0Retries (Write) : 0Errors (Read) : 23Errors (Write) : 0 PROBLEMS SUMMARY Failed Indicators (life-span / pre-fail) : 1 (1 / 0)Failing Indicators (life-span / pre-fail) : 3 (3 / 0)Warnings (life-span / pre-fail) : 1 (1 / 0)Recently failed Self-tests (Short / Full) : 0 (0 / 0)I/O Error Count : 23 (23 / 0)Time in Under temperature : 0 minutesTime in Over temperature : 0 minutes IMPORTANT HEALTH INDICATORS ID NAME RAW VALUE STATUS5 Reallocated Sector Count 0xEF50 75.0% OK187 Reported Uncorrectable Errors 65,535 1.0% Failing197 Current Pending Sector Count 5,256 68.0% Failing198 Offline Uncorrectable Sector Count 5,256 68.0% Failing199 UDMA CRC Error Count 0 100% OK241 Total LBAs Written 74,589,541,612 (38.2 TB) 100% OK TEMPERATURE INFORMATION (CELSIUS) Current Temperature : 29Power Cycle Min Temperature : 29Power Cycle Max Temperature : 29Lifetime Min Temperature : 10Lifetime Max Temperature : 54Recommended Min Temperature : 3Recommended Max Temperature : 62Temperature Min Limit : 0Temperature Max Limit : 65 DRIVE HEALTH INDICATORS ID | NAME | TYPE | UPDATE | RAW VALUE | VALUE | THRESHOLD | WORST | LAST MODIFIED | STATUS1 Raw Read Error Rate Pre-fail online 0x70D52ED 78 6 73 19/5/2022 5:13 am 63.2% OK3 Spin Up Time Pre-fail online 0 94 0 94 19/5/2022 5:13 am 94.0% OK4 Start Stop Count Life-span online 31,957 69 20 69 19/5/2022 5:13 am 61.3% OK5 Reallocated Sector Count Pre-fail online 0xEF50 84 36 51 19/5/2022 5:13 am 75.0% OK7 Seek Error Rate Pre-fail online 0x19986DFB 86 30 60 19/5/2022 5:13 am 100% OK9 Power On Hours Life-span online 21,893 76 0 76 19/5/2022 5:13 am 76.0% OK10 Spin Retry Count Pre-fail online 0 100 97 100 19/5/2022 5:13 am 100% OK12 Power Cycle Count Life-span online 43,955 58 20 58 19/5/2022 5:13 am 47.5% OK184 End-to-End Error Life-span online 8 92 99 92 19/5/2022 5:13 am 0% Failed187 Reported Uncorrectable Errors Life-span online 65,535 1 0 1 19/5/2022 5:13 am 1.0% Failing188 Command Timeout Life-span online 321 99 0 67 19/5/2022 5:13 am 99.0% Warning189 High Fly Writes Life-span online 31 69 0 69 19/5/2022 5:13 am 100% OK190 Airflow Temperature Celsius Life-span online 29 71 45 46 19/5/2022 5:13 am 47.3% OK191 G-Sense Error Rate Life-span online 0 100 0 100 19/5/2022 5:13 am 100% OK192 Power-Off Retract Count Life-span online 415 100 0 100 19/5/2022 5:13 am 100% OK193 Load Cycle Count Life-span online 44,019 78 0 78 19/5/2022 5:13 am 78.0% OK194 Temperature (Celsius) Life-span online 29 71 35 46 19/5/2022 5:13 am 55.4% OK197 Current Pending Sector Count Life-span online 5,256 68 0 1 19/5/2022 5:13 am 68.0% Failing198 Offline Uncorrectable Sector Count Life-span offline 5,256 68 0 1 19/5/2022 5:13 am 68.0% Failing199 UDMA CRC Error Count Life-span online 0 200 0 200 19/5/2022 5:13 am 100% OK240 Head Flying Hours Life-span offline 25,484 100 0 253 19/5/2022 5:13 am 100% OK241 Total LBAs Written Life-span offline 74,589,541,612 (38.2 TB) 100 0 253 19/5/2022 5:13 am 100% OK242 Total LBAs Read Life-span offline 4,406,628,187,644 (2.3 PB) 100 0 253 19/5/2022 5:13 am 100% OK DRIVE ERROR LOG

| TIME OCCURRED | ERRORS | PRIOR COMMAND5 21892 hours UNKNOWN ERROR READ FPDMA QUEUED4 21892 hours UNKNOWN ERROR READ FPDMA QUEUED3 21892 hours UNKNOWN ERROR READ FPDMA QUEUED2 21892 hours UNKNOWN ERROR READ FPDMA QUEUED1 21892 hours UNC READ DMA EXT

DRIVE SELF-TEST LOG self-test log is empty SYSTEM INFORMATION Report Timestamp : 19 May 2022 5:22:50 am AESTReport Timestamp (ISO 8601 format) : 2022-05-19T05:22:50Application Name : DriveDxApplication Version : 1.11.0.730Application SubBuild : 0Application Edition : StandaloneApplication Website : https://binaryfruit.com/drivedxDriveDx Knowledge Base Revision : 101/101Computer Name : iMacHost Name : iMacComputer Model : iMac18,3OS Boot Time : 2022-05-18T22:24:25Time Since Boot : 06h 58m 25sOS Name : macOSOS Version : 10.16.0OS Build : 21E258OS Kernel Version : Darwin 21.4.0SAT SMART Driver Version : N/AATA Command Support Tolerance : verypermissive Number of drives in report : 1 DRIVE 1 OF 1 Last Checked : 19 May 2022 5:13:59 am AESTLast Checked (ISO 8601 format) : 2022-05-19T05:13:59Advanced SMART Status : OKOverall Health Rating : GOOD 100%SSD Lifetime Left Indicator : AVERAGE 50.0%Issues found : 0Serial Number : S3CWNY0J221876WWN Id :Volumes :Device Path : /dev/disk0Total Capacity : 121.3 GB (121,332,826,112 Bytes)Model Family : Apple/Samsung NVMe L-series SSDModel : APPLE SSD SM0128LFirmware Version : CXS7CA0QDrive Type : SSDPower On Time : 4,972 hours (6 months 27 days 4 hours)Power Cycles Count : 29,497Current Power Cycle Time : 7.0 hours DEVICE CAPABILITIES S.M.A.R.T. support enabled : yesDriveDx Active Diagnostic Config : Apple/Samsung NVMe SSD L-series config [ssd.nvme.apple.sm.l]Sector Logical Size : 4096Sector Physical Size : 4096Physical Interconnect : PCI-Express (PCIe)Logical Protocol : NVM-Express (NVMe)Removable : noEjectable : noNVMe Revision Supported : 1.10PCI Vendor Id : 0x144dThermal Throttling Supported : noVolatile Write Cache Supported : yesMaximum Data Transfer Size : 256 PagesLog Page Attributes : 0x0Format NVM Attributes : 0x3Optional Admin Command Support : 0x0Optional NVM Command Support : 0x1f (Compare, Wr_Unc, DS_Mngmt, Wr_Zero, Save/Sel_Feat)Number of Power States Supported : 2Error Log Page Entries : 63Keep Alive Support : 0Total NVMe Capacity : -Unallocated NVMe Capacity : -Number of NVMe Namespaces : 1I/O Path : IOService:/AppleACPIPlatformExpert/PCI0@0/AppleACPIPCI/RP17@1B/IOPP/SSD0@0/IONVMeController/IONVMeBlockStorageDevice@1[Known device ]: yes[Drive State Flags ]: 0x0 CURRENT POWER CYCLE STATISTICS Time since computer startup : 6 hoursData Read : 653,848,576 bytes (653.8 MB)Data Written : 92,028,928 bytes (92.0 MB)Data Read/Write Ratio : 7.10Data Read/hour : 93.8 MB/hourData Write/hour : 13.2 MB/hourOperations (Read) : 138,798Read IOPS : 3,972Operations (Write) : 4,918Write IOPS : 141Operations Read/Write Ratio : 28Throughput per operation (Read) : 4.7 KB/OpThroughput per operation (Write) : 18.7 KB/OpLatency Time (Read) : 0 nsLatency Time (Write) : 0 nsRetries (Read) : 0Retries (Write) : 0Errors (Read) : 0Errors (Write) : 0 PROBLEMS SUMMARY Failed Indicators (life-span / pre-fail) : 0 (0 / 0)Failing Indicators (life-span / pre-fail) : 0 (0 / 0)Warnings (life-span / pre-fail) : 0 (0 / 0)I/O Error Count : 0 (0 / 0) IMPORTANT HEALTH INDICATORS ID NAME RAW VALUE STATUS7 Data Units Written 129,418,339 (66.3 TB) 100% OK14 Media and Data Integrity Errors 0 100% OK TEMPERATURE INFORMATION (CELSIUS) Current Temperature : 36Power Cycle Min Temperature : 36Power Cycle Max Temperature : 36Lifetime Min Temperature : 36Lifetime Max Temperature : 36Recommended Min Temperature : 5Recommended Max Temperature : 65Temperature Min Limit : 5Temperature Max Limit : 70 DRIVE HEALTH INDICATORS ID | NAME | TYPE | UPDATE | RAW VALUE | VALUE | THRESHOLD | WORST | LAST MODIFIED | STATUS2 Composite Temperature Life-span online 36 (36 °C) 64 30 64 19/5/2022 5:13 am 48.6% OK3 Available Spare Pre-fail online 100 100 10 100 19/5/2022 5:13 am 100% OK5 Life Percentage Used Life-span online 50 50 0 50 19/5/2022 5:13 am 50.0% OK6 Data Units Read Life-span online 138,869,905 (71.1 TB) 100 0 100 19/5/2022 5:13 am 100% OK7 Data Units Written Life-span online 129,418,339 (66.3 TB) 100 0 100 19/5/2022 5:13 am 100% OK8 Host Read Commands Life-span online 3,645,024,451 100 0 100 19/5/2022 5:13 am 100% OK9 Host Write Commands Life-span online 4,088,558,941 100 0 100 19/5/2022 5:13 am 100% OK10 Controller Busy Time Life-span online 14,519 (14,519 minutes) 100 0 100 19/5/2022 5:13 am 100% OK11 Power Cycles Life-span online 29,497 100 0 100 19/5/2022 5:13 am 100% OK12 Power On Hours Life-span online 4,972 (4,972 hours) 100 0 100 19/5/2022 5:13 am 100% OK13 Unsafe Shutdowns Life-span online 223 100 0 100 19/5/2022 5:13 am 100% OK14 Media and Data Integrity Errors Pre-fail online 0 100 0 100 19/5/2022 5:13 am 100% OK15 Error Information Log Entries Pre-fail online 0 100 0 100 19/5/2022 5:13 am 100% OK16 Warning Composite Temperature Time Life-span online 0 (0 minutes) 100 0 100 19/5/2022 5:13 am 100% OK17 Critical Composite Temperature Time Life-span online 0 (0 minutes) 100 0 100 19/5/2022 5:13 am 100% OK DRIVE ERROR LOG error log is empty

Yes! You don’t need the Fusion blade SSD in your system. The easiest way is after backing up your stuff using your external drive (booting up under it reformat each drive that should make it clear which drive is having problems. You could also check the blade SSD using a tool like DriveDX which lets you see the SSD’s health. You don’t need to take it out once it’s deactivated when you put in the new SATA SSD drive.