IBM
IBM 59Y3957 Xeon DP 5500 X5550 2.66 GHz processor upgrade
A quad-core Xeon processor upgrade for Socket B LGA-1366 servers, running at 2.66 GHz with 8 MB L3 cache and 95 W TDP
- Electrical Outlet Plug TypeProcessor Upgrade
- Quad-core design handles parallel workloads efficiently
- 66 GHz clock speed delivers responsive processing
- 8 MB L3 cache reduces memory latency
- 40 GT/s QuickPath Interconnect speeds data transfer
- 95 W thermal design power balances performance and heat
Xeon DP 5500 X5550 upgrade
This refurbished IBM processor upgrade delivers a quad-core Intel Xeon DP 5500 X5550 running at 2.66 GHz for Socket B LGA-1366 servers. It targets administrators refreshing compatible enterprise platforms that require Nehalem-era performance within existing infrastructure. The 45 nm process and 95 W thermal design power suit dense rack environments where power density matters.
QuickPath Interconnect 6.40 GT/s limit
The processor communicates over a QuickPath Interconnect running at 6.40 GT/s, which sets the practical bandwidth ceiling for multi-socket coherence traffic. Workloads that saturate inter-socket links will hit this ceiling before newer platforms would, so scaling beyond two sockets yields diminishing returns. Memory bandwidth is similarly bound to the integrated controller tied to this interconnect speed.
8 MB L3 cache and 95 W headroom
The 8 MB shared L3 cache comfortably handles typical virtualisation and database working sets that fit within its capacity, while the 95 W TDP provides thermal headroom for sustained loads in cooled racks. Workloads with larger per-core footprints or higher thread counts will exhaust cache space and push thermal limits beyond what this generation can sustain.
Socket B LGA-1366 constraint
This upgrade fits only Socket B LGA-1366 platforms, so it cannot serve systems built for later Xeon families or different socket types. Buyers needing support for newer instruction sets, higher core counts, or different memory architectures must select a different processor line. The 1.4 V input voltage and 75 °C thermal specification further define the operating envelope for compatible boards.
Highlights
- Quad-core design handles parallel workloads efficiently
- 66 GHz clock speed delivers responsive processing
- 8 MB L3 cache reduces memory latency
- 40 GT/s QuickPath Interconnect speeds data transfer
- 95 W thermal design power balances performance and heat
Specifications
| Brand | IBM |
|---|---|
| Electrical Outlet Plug Type | Processor Upgrade |
| Shipping weight | 0.91 kg |
| Package size | 127 × 127 × 51 mm |
Questions about this item
Which variant of the 59Y3957 matches the Xeon DP 5500 X5550 2.66 GHz specification?
The 59Y3957 is a single processor upgrade with a quad-core X5550 running at 2.66 GHz, 1 MB L2 cache, 8 MB L3 cache, and a 6.40 GT/s QuickPath Interconnect.
What does the 2.66 GHz clock speed deliver in a live server?
Four cores at 2.66 GHz with 8 MB shared L3 cache provide strong multi-threaded throughput for virtualization and database workloads on Socket B LGA-1366 platforms.
How does the 6.40 GT/s QuickPath Interconnect limit real-world bandwidth?
The 6.40 GT/s link sets the peak processor-to-processor and processor-to-chipset transfer rate, capping memory and I/O scaling in dual-socket configurations.
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