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HighPoint’s $399 Rocket 1604L is a PCIe Gen5 x16 add-in board housing four M.2 NVMe SSDs, each on an independent Gen5 x4 lane. Testing with four Samsung 9100 PRO 4TB drives hit 55.6GB/s aggregate 128K sequential read and 10.1M 4K random write IOPS — nearly matching the native throughput of the SSDs when plugged directly into motherboard slots. Its core selling point: extra M.2 slots with negligible performance loss.
Unlike passive bifurcation adapters or PCIe switch cards, the 1604L relies on an Astera Labs PT5161LRS signal retimer in the physical-layer data path, regenerating Gen5 signals between the host and each M.2 connector. Gen4 passive adapters work reliably, but Gen5’s 32GT/s signaling suffers signal degradation over longer traces, forcing links to downshift to Gen4 or throw errors under heavy load. Retimers fix this without the extra power, latency and cost of full PCIe switches. The tradeoff: the motherboard PCIe slot must support x4/x4/x4/x4 lane bifurcation, as the retimer cannot virtualize lanes on its own.
This model joins HighPoint’s Gen5 adapter lineup: the switch-based Rocket 1604A works on any x16 slot without bifurcation, while the Rocket 7604A adds hardware bootable RAID. The 1604L is the most streamlined variant, with no onboard RAID stack or dedicated drivers. The OS detects four standalone NVMe drives; users deploy mdadm, Storage Spaces or ZFS for array functionality. HighPoint targets the card at servers running M.2 AI accelerators like Hailo-8, though general storage use is far more widespread. It adopts a compact full-height half-length PCB (40% shorter than typical quad-M.2 Gen5 cards), paired with a full aluminum heatsink, drive thermal padding, quiet integrated fan and ventilated bracket. Firmware monitors per-port lane allocation, power draw and hardware health, plus per-SSD presence and activity LEDs.
The mandatory bifurcation support is a critical purchasing caveat. Most consumer motherboards either cannot split an x16 slot into four x4 segments or steal lanes from the primary GPU. The card fits Threadripper TRX50/WRX90, Xeon W, EPYC and standard Xeon servers, where x4/x4/x4/x4 is a simple BIOS toggle and spare x16 slots are readily available — matching the HEDT Threadripper test rig used for evaluation.
Rocket 1604L Key Specs
- Interface: PCIe 5.0 x16
- Controller: Astera Labs PT5161LRS retimer
- Mode: Requires host x4/x4/x4/x4 bifurcation
- Ports: 4× M.2 NVMe (PCIe 5.0 x4 per slot; supports 2242/2260/2280 SSDs or AI accelerator modules)
- Max aggregate bandwidth: 64GB/s
- RAID: No onboard hardware RAID (software RAID via OS)
- Form factor: Full-height, half-length
- Cooling: Full aluminum heatsink, integrated fan, thermal pads, ventilated slot bracket
- Monitoring: Per-port power, lane status and hardware health via firmware; drive activity LEDs
- OS compatibility: Native NVMe support for x86 Intel/AMD and ARM platforms
- Retail price: $399
Build & Installation
Its condensed PCB differentiates it from bulkier Gen4 quad-M.2 adapters. Installation is standard: remove the heatsink, mount four M.2 drives with thermal pads, then reattach the cooling assembly. The built-in fan exhausts through the ventilated bracket, eliminating thermal throttling during 60-minute sustained load testing.
Test Platform
- CPU: AMD Ryzen Threadripper 7980X (64C/128T)
- Motherboard: ASUS Pro WS TRX50-SAGE WIFI
- RAM: 128GB DDR5-6400
- Storage: 1TB PCIe 4.0 boot SSD + four Samsung 9100 PRO 4TB SSDs on the 1604L
- OS: Ubuntu Server 24.04
Each Samsung drive is rated for 14,800MB/s sequential read, 13,400MB/s sequential write, 2.2M random read IOPS and 2.6M random write IOPS, for a theoretical total of 59.2GB/s read and 10.4M random write IOPS. The Gen5 x16 slot caps out at ~63GB/s usable bandwidth, so the SSDs — not the adapter — form the performance ceiling.
Benchmarks ran FIO 3.36 with io_uring, 5% LBA working set, 60-second test durations and 5-second ramp periods. Sequential workloads used QD64 with one job per drive; 4K random tests used 16 jobs per drive (QD32). These are client-focused burst test parameters rather than enterprise steady-state benchmarks.
Performance Results
Sequential Aggregate (4 Drives)
128K Read: 424K IOPS / 55.6GB/s, avg latency 604µs, 99th percentile 906µs
128K Write: 279K IOPS / 36.5GB/s, avg latency 918µs, 99th percentile 1303µs
64K Read: 668K IOPS / 43.8GB/s, avg latency 383µs, 99th percentile 570µs
64K Write: 462K IOPS / 30.3GB/s, avg latency 553µs, 99th percentile 914µs
128K Write: 279K IOPS / 36.5GB/s, avg latency 918µs, 99th percentile 1303µs
64K Read: 668K IOPS / 43.8GB/s, avg latency 383µs, 99th percentile 570µs
64K Write: 462K IOPS / 30.3GB/s, avg latency 553µs, 99th percentile 914µs
The 55.6GB/s 128K read throughput hits 94% of the combined SSD rating, proving the retimer architecture preserves full drive performance with consistent sub-millisecond latency and sustained >99% drive utilization. Sequential write speeds fall short of the total theoretical 53.6GB/s ceiling because vendor specs reflect short pSLC cache bursts, while the sustained 60-second tests exhaust this cache.
4K Random Aggregate (4 Drives)
4K Read: 8.83M IOPS / 36.2GB/s, avg latency 231µs, 99th percentile 553µs
4K Write: 10.1M IOPS / 41.5GB/s, avg latency 202µs, 99th percentile 461µs
4K Write: 10.1M IOPS / 41.5GB/s, avg latency 202µs, 99th percentile 461µs
Random read IOPS nearly exactly matches the combined SSD rating, while random write reaches 97% of the theoretical maximum; the smaller 5% working set keeps SSD caches highly efficient. Running nearly 10M total IOPS consumes ~60% system CPU capacity, a heavy workload for workstations to sustain.
Conclusion
Test data confirms the Rocket 1604L adds almost no overhead, delivering 94–100% of the four SSDs’ combined rated performance. The $399 price tag competes against cheap passive bifurcation adapters, yet the retimer’s signal integrity benefits are essential for stable Gen5 operation with high-speed flash. At $100 per cooled, monitored Gen5 M.2 slot, it undercuts switch-based alternatives without sacrificing per-port bandwidth.
Ideal Buyers
Owners of TRX50, WRX90, Xeon W and x86 servers needing 16TB+ Gen5 flash in a single PCIe slot for media editing, AI dataset staging or scratch storage, who rely on OS-managed arrays instead of hardware RAID.
Not Recommended
Systems lacking x4/x4/x4/x4 bifurcation support (choose Rocket 1604A instead); users requiring bootable hardware RAID (opt for Rocket 7604A); and anyone only deploying PCIe 4.0 SSDs, where retimer functionality offers little value.
Beijing Qianxing Jietong Technology Co., Ltd.
Sandy Yang/Global Strategy Director
WhatsApp / WeChat: +86 13426366826
Email: yangyd@qianxingdata.com
Website: www.qianxingdata.com/www.storagesserver.com
Business Focus:
ICT Product Distribution/System Integration & Services/Infrastructure Solutions
With 20+ years of IT distribution experience, we partner with leading global brands to deliver reliable products and professional services.
“Using Technology to Build an Intelligent World”Your Trusted ICT Product Service Provider!
Sandy Yang/Global Strategy Director
WhatsApp / WeChat: +86 13426366826
Email: yangyd@qianxingdata.com
Website: www.qianxingdata.com/www.storagesserver.com
Business Focus:
ICT Product Distribution/System Integration & Services/Infrastructure Solutions
With 20+ years of IT distribution experience, we partner with leading global brands to deliver reliable products and professional services.
“Using Technology to Build an Intelligent World”Your Trusted ICT Product Service Provider!