Xeon E3-1205 v6 vs Xeon E5649

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 E3-1205 v6 vs Xeon E5649 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 E3-1205 v6 vs Xeon E5649: Pros, Cons & Final Verdict

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

Xeon E3-1205 v6

2017

Why buy it

✅+0.4% higher PassMark.
✅Draws 65W instead of 80W, a 15W reduction.

Trade-offs

❌Worse for gaming: lower average FPS than Xeon E5649 across 49 shared CPU benchmark tests.
❌Smaller total L3 cache (8 MB vs 12 MB).

Xeon E5649

2011

Why buy it

✅Better for gaming: +19.5% higher average FPS across 49 shared CPU benchmark tests.
✅+50% larger total L3 cache (12 MB vs 8 MB).

Trade-offs

❌Lower PassMark (5,659 vs 5,682).
❌Launch MSRP is still $774 MSRP, while Xeon E3-1205 v6 mostly shows up through inconsistent older-market listings.
❌23.1% higher power demand at 80W vs 65W.

Quick Answers

So, is Xeon E3-1205 v6 better than Xeon E5649?

It depends on what you want from the system. For gaming, Xeon E5649 is ahead with a 19.5% average FPS lead across 49 shared CPU game tests in our data. For rendering, compiling, streaming, and heavier multitasking, Xeon E3-1205 v6 pulls ahead with 0.4% better PassMark. Xeon E5649 also has the bigger cache pool with 50% larger total L3 cache (12 MB vs 8 MB).

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

For streaming, content creation, and heavier multitasking, Xeon E3-1205 v6 is the stronger fit. You are getting 0.4% better PassMark, backed by 4 cores and 4 threads.

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

Xeon E3-1205 v6 is still the faster CPU overall, but Xeon E5649 is easier to justify if budget matters more than peak performance. Xeon E3-1205 v6 comes in at an unclear MSRP at unclear MSRP versus $774 MSRP, and it still gives you 0.4% better PassMark. The compromise is that Xeon E5649 is still the better pure gaming CPU with a 19.5% average FPS lead across 49 shared CPU game tests in our data. Xeon E5649 is also 100.0% better value on MSRP (7.3 vs 0.0 PassMark/$), which is why it can still make sense for tighter-budget builds on paper.

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

Xeon E3-1205 v6 makes more sense long term for 2026 and beyond. You are getting a newer CPU generation (2017 vs 2011) and more multi-core headroom with 4 cores / 4 threads instead of 6/12. That extra compute headroom is more likely to matter as games, background tasks, and creator workloads get heavier.

Xeon E3-1205 v6 vs Xeon E5649 Technical Specifications

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

Xeon E3-1205 v6

The Xeon E3-1205 v6 is manufactured by Intel. It was released in 28 March 2017 (8 years ago). It is based on the Kaby Lake (2016−2019) architecture. It features 4 cores and 4 threads. Base frequency is 3 GHz, with boost up to 3 GHz. L3 cache: 8 MB. L2 cache: 1 MB. Built on 14 nm process technology. Socket: LGA1151. Thermal design power (TDP): 65 Watt. Memory support: DDR4-2400, DDR3L-1866. Passmark benchmark score: 5,682 points. Launch price was $193.

Xeon E5649

The Xeon E5649 is manufactured by Intel. It was released in 14 February 2011 (14 years ago). It is based on the Westmere-EP (2010−2011) architecture. It features 6 cores and 12 threads. Base frequency is 2.53 GHz, with boost up to 2.93 GHz. L3 cache: 12288 kB (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: 5,659 points. Launch price was $45.

⚡

Processing Power

The Xeon E3-1205 v6 packs 4 cores / 4 threads, while the Xeon E5649 offers 6 cores / 12 threads — the Xeon E5649 has 2 more cores. Boost clocks reach 3 GHz on the Xeon E3-1205 v6 versus 2.93 GHz on the Xeon E5649 — a 2.4% clock advantage for the Xeon E3-1205 v6 (base: 3 GHz vs 2.53 GHz). The Xeon E3-1205 v6 uses the Kaby Lake (2016−2019) architecture (14 nm), while the Xeon E5649 uses Westmere-EP (2010−2011) (32 nm). In PassMark, the Xeon E3-1205 v6 scores 5,682 against the Xeon E5649's 5,659 — a 0.4% lead for the Xeon E3-1205 v6. L3 cache: 8 MB on the Xeon E3-1205 v6 vs 12288 kB (total) on the Xeon E5649.

Feature	Xeon E3-1205 v6	Xeon E5649
Cores / Threads	4 / 4	6 / 12+50%
Boost Clock	3 GHz+2%	2.93 GHz
Base Clock	3 GHz+19%	2.53 GHz
L3 Cache	8 MB	12288 kB (total)+50%
L2 Cache	1 MB+300%	256 kB (per core)
Process	14 nm-56%	32 nm
Architecture	Kaby Lake (2016−2019)	Westmere-EP (2010−2011)
PassMark	5,682	5,659
Geekbench 6 Single	—	415
Geekbench 6 Multi	—	2,109

🧠

Memory & Platform

The Xeon E3-1205 v6 uses the LGA1151 socket (PCIe 3.0), while the Xeon E5649 uses LGA1366 (PCIe 5.0) — making them incompatible on the same motherboard.

Feature	Xeon E3-1205 v6	Xeon E5649
Socket	LGA1151	LGA1366
PCIe Generation	PCIe 3.0	PCIe 5.0+67%
Max RAM Speed	—	DDR3 1333 MHz
Max RAM Capacity	—	288 GB
RAM Channels	—	3
ECC Support	—	Yes
PCIe Lanes	—	0