Xeon D-1520 vs Xeon E5645

PassMark CPU Mark evaluates processor speed through complex mathematical computations. It provides a reliable metric to compare multi-core performance, where higher scores indicate faster processing for multitasking, gaming, and heavy workloads.

Xeon D-1520 vs Xeon E5645 FPS Benchmarks

Predicted gaming performance across popular games. Tested paired with GeForce RTX 5090 to isolate CPU performance.

Search any supported game below to compare 1080p FPS for both components.

Xeon D-1520 vs Xeon E5645: Pros, Cons & Final Verdict

See where each CPU makes more sense in practice: gaming, heavier work, platform cost, power draw, and upgrade path.

Xeon D-1520

2015

Why buy it

✅Draws 45W instead of 80W, a 35W reduction.

Trade-offs

❌Lower PassMark (4,917 vs 4,942).
❌Smaller total L3 cache (1.5 MB vs 12 MB).

Xeon E5645

2010

Why buy it

✅+700% larger total L3 cache (12 MB vs 1.5 MB).

Trade-offs

❌Launch MSRP is still $294 MSRP, while Xeon D-1520 mostly shows up through inconsistent older-market listings.
❌77.8% higher power demand at 80W vs 45W.

Quick Answers

So, is Xeon E5645 better than Xeon D-1520?

Yes. Xeon E5645 is the better all-around CPU here. It gives you a 1.3% average FPS lead across 47 shared CPU game tests in our data and 0.5% better PassMark, which is enough to make it the stronger overall pick.

Which one is better for gaming?

If gaming is the priority, Xeon E5645 is the better pick. According to our tests, it delivers 1.3% more average FPS across 47 shared CPU game tests.

Which one is better for streaming, content creation, and heavy multitasking?

For streaming, content creation, and heavier multitasking, Xeon E5645 is the stronger fit. You are getting 0.5% better PassMark, backed by 6 cores and 12 threads. It also has the larger cache pool with 700% larger total L3 cache (12 MB vs 1.5 MB).

Which one is the smarter buy today, not just the cheaper CPU?

Xeon E5645 is the better buy right now. Xeon E5645 comes in at an unclear MSRP at $294 MSRP versus unclear MSRP, and it still gives you a 1.3% average FPS lead across 47 shared CPU game tests in our data. It is also 100.0% better value on MSRP (16.8 vs 0.0 PassMark/$), so you are getting the faster CPU without taking a value hit on paper.

Which one is more future-proof for 2026 and beyond?

Xeon D-1520 makes more sense long term for 2026 and beyond. You are getting a newer CPU generation (2015 vs 2010). That makes it the safer long-term bet.

Xeon D-1520 vs Xeon E5645 Technical Specifications

Side-by-side specs, architecture details, clocks, memory, power, and platform differences.

Xeon D-1520

The Xeon D-1520 is manufactured by Intel. It was released in 9 March 2015 (10 years ago). It is based on the Broadwell (2015−2019) architecture. It features 4 cores and 8 threads. Base frequency is 2.2 GHz, with boost up to 2.6 GHz. L3 cache: 1.5 MB (per core). L2 cache: 256K (per core). Built on 14 nm process technology. Socket: FCBGA1667. Thermal design power (TDP): 45 Watt. Memory support: DDR4. Passmark benchmark score: 4,917 points. Launch price was $199.

Xeon E5645

The Xeon E5645 is manufactured by Intel. It was released in 16 March 2010 (15 years ago). It is based on the Westmere-EP (2010−2011) architecture. It features 6 cores and 12 threads. Base frequency is 2.4 GHz, with boost up to 2.67 GHz. L3 cache: 12 MB (total). L2 cache: 256 kB (per core). Built on 32 nm process technology. Socket: LGA1366. Thermal design power (TDP): 80 Watt. Memory support: DDR3. Passmark benchmark score: 4,942 points. Launch price was $294.

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Processing Power

The Xeon D-1520 packs 4 cores / 8 threads, while the Xeon E5645 offers 6 cores / 12 threads — the Xeon E5645 has 2 more cores. Boost clocks reach 2.6 GHz on the Xeon D-1520 versus 2.67 GHz on the Xeon E5645 — a 2.7% clock advantage for the Xeon E5645 (base: 2.2 GHz vs 2.4 GHz). The Xeon D-1520 uses the Broadwell (2015−2019) architecture (14 nm), while the Xeon E5645 uses Westmere-EP (2010−2011) (32 nm). In PassMark, the Xeon D-1520 scores 4,917 against the Xeon E5645's 4,942 — a 0.5% lead for the Xeon E5645. L3 cache: 1.5 MB (per core) on the Xeon D-1520 vs 12 MB (total) on the Xeon E5645.

Feature	Xeon D-1520	Xeon E5645
Cores / Threads	4 / 8	6 / 12+50%
Boost Clock	2.6 GHz	2.67 GHz+3%
Base Clock	2.2 GHz	2.4 GHz+9%
L3 Cache	1.5 MB (per core)	12 MB (total)+700%
L2 Cache	256K (per core)	256 kB (per core)
Process	14 nm-56%	32 nm
Architecture	Broadwell (2015−2019)	Westmere-EP (2010−2011)
PassMark	4,917	4,942

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Memory & Platform

The Xeon D-1520 uses the FCBGA1667 socket (PCIe 3.0), while the Xeon E5645 uses LGA1366 (PCIe 5.0) — making them incompatible on the same motherboard.

Feature	Xeon D-1520	Xeon E5645
Socket	FCBGA1667	LGA1366
PCIe Generation	PCIe 3.0	PCIe 5.0+67%
Max RAM Speed	—	DDR3-1333
Max RAM Capacity	—	288 GB
RAM Channels	—	3
ECC Support	—	Yes
PCIe Lanes	—	0