The TR-004 USB 3.0 RAID expansion enclosure allows you to expand the capacity of your QNAP NAS and PC. The TR-004 can also be utilized as a DAS (Direct-attached Storage) device, allowing you to directly access its content just by connecting it via USB. The TR-004 features four 3.5-inch SATA drive bays with multiple RAID configuration options and USB 3.0 Type-C connectivity to bring you a highly reliable and secure storage capacity expansion solution. Key Features

The TR-004U does not support the following: the TS-128, TS-228, TS-131, TS-231, TS-431, TS-431U, and NAS models that cannot be updated to QTS 4.3.6 (or later). I haven't seen a solution in this thread, and I have the same issue since I have had the TR-004 in September. My configuration and use case are as follows: QNAP reserves the right to replace partial parts or accessories if the original is no longer available from its manufacturer/supplier. Any replacement would be fully tested and verified to meet strict compatibility and stability guidelines and will deliver identical performance to the original.Drives can only be migrated from one TR-004U to another TR-004U. The files and data stored on drives moved to/from a NAS (or another device) will not be recognized.

Second, when I perform a write operation against the drive, while I perform a read operation, the speed of the read drops to ~40MB/s while the write is around ~30-40MB/s. Seems like a pretty severe penalty that shouldn't be the case. Note: Use only QNAP memory modules to maintain system performance and stability. For NAS devices with more than one memory slot, use QNAP modules with identical specifications.

Optional Accessories

did install 4 hdds into tr004 and setting up a raid5? and what is it's current setup like with the 2 existing hard drives on the tr-004? For myself i just power off my external tl-d400s. My nas is setup for 24/7 that never spins down, because my usage patterns would probly trigger spinups/downs too frequently, so my case it's probly not worth it. also i'm not aware if whether my own device can keep the tl-d400s in a spindown state when it's not even doing anything, so i just use the power off just to be sure. OR alternatively you can set it up as a raid5 on standalone mode using the windows qnap utility app that can create the raid5 without using qts. I believe that you can still connect this to the QNAP and use as an external USB. But whenever you want to manage it, you need to connect to a windows pc and use the qnap utility app for tr-004 i presume. Use Storage & Snapshots Manager to configure the TR-004 as a storage expansion unit for your QNAP NAS. In addition to RAID configuration, the NAS expansion storage mode supports various NAS functions, including storage pools and snapshots. By choosing external storage mode, you can use the TR-004 as a DAS. I had this same issue (30MB/s read and write speeds) and resolved it by uninstalling the USB drivers, rebooting my Win 10 PC, and allowing the system to reinstall the drivers. Now data transfers are around 200MB/s. I really don't think it has anything to do with supposed poor performance by the TR-004. The box works just fine, as advertised. Sometimes USB drivers need to be reinstalled and reinitialized, particularly when different devices (such as USB Headphones or a USB Mouse) are exchanged for another device (such as a mass storage device).