Quick Verdict
A niche OEM processor that offered better integrated graphics in a low-power package, now mostly useful for exact-match legacy repairs.
Overview
Launch
2011
Status
DiscontinuedGeneration
2nd Gen
Market
Desktop
The Intel Core i5-2405S is a specialized 65W quad-core processor that distinguishes itself from the i5-2400S through its integrated graphics. While sharing the same 2.5 GHz base clock and 3.3 GHz turbo boost, Intel equipped this chip with the Intel HD 3000 graphics processor instead of the HD 2000. The HD 3000 features 12 Execution Units, doubling the graphics rendering capabilities. This made the i5-2405S an ideal choice for small form factor business PCs that required slightly better graphical throughput for entry-level 3D applications or dual-display setups without adding a dedicated GPU.
The Core i5-2405S combines a 65W TDP with 4 cores and the upgraded HD 3000 iGPU, targeting slim PCs that need better than basic display capabilities.
Specifications
Performance
CPU performance is identical to the i5-2400S, adequate for legacy apps.
VM performance is constrained by the 4-thread limit.
HD 3000 can handle very old games, but nothing modern.
Excellent power metrics for a quad-core chip of its era.
- •HD 3000 is noticeably faster than HD 2000 in legacy titles
- •Still lacks DirectX 12 support
- •Not viable for 3D gaming past 2012 standards
- •No AI acceleration capabilities
Architecture
32nm
Process Node
Sandy Bridge
Codename
4C / 4T
Core Config
6 MB
L3 Cache
65 W
TDP
Architecture Overview
Fabricated on the 32nm node, the i5-2405S uses the standard 216 mm² Sandy Bridge quad-core die. Architecturally, it is nearly identical to the i5-2400S, featuring a locked 25x multiplier, 6 MB of shared L3 cache, and a dual-channel DDR3 memory controller. The critical difference lies in the integrated graphics die, where the HD 3000 GPU operates at a higher dynamic frequency. This upgrade provided meaningful improvements in hardware-accelerated video transcoding via Quick Sync and basic Windows Aero/GUI rendering compared to its HD 2000 counterparts.
CPU Design
4 cores without Hyper-Threading, paired with an enhanced 12 EU GPU.
Memory Subsystem
Dual-channel DDR3-1333 memory controller.
PCIe & I/O
16 lanes of PCIe 2.0.
Overclocking
Locked multiplier; BCLK adjustments are the only option.
- Upgraded from HD 2000 to HD 3000 graphics
- Two additional physical cores
- Massive IPC improvement
Key Highlights
- Intel HD 3000 integrated graphics
- Quick Sync Video support
- Low 65W power draw
- Full 6 MB L3 cache
- Rare and potentially expensive on the used market
- No Hyper-Threading
- Lower clocks than standard 95W parts
- Lacks AVX2
- Not Windows 11 compatible
History
Released in May 2011, a few months after the standard Sandy Bridge launch, the i5-2405S filled a very specific OEM demand. System builders requested a low-power quad-core CPU with better-than-basic graphics for all-in-one PCs and compact media centers. By creating this specific SKU, Intel allowed OEMs to market 'HD graphics capable' small desktops without incurring the cost or thermal output of a dedicated graphics card.
It was a relatively rare SKU compared to the standard i5-2400 or i5-2400S, primarily finding a home in premium small form factor systems like the Apple iMac, where space and thermal limits were incredibly strict.
Improvements over Previous Generation
- Upgraded from HD 2000 to HD 3000 graphics
- Two additional physical cores
- Massive IPC improvement
Alternatives & Competitors
Should You Buy It?
Not Recommended for the right buyer
Replacing a failed CPU in a 2011 Apple iMac or premium AIO
Avoid if…
- Building a standard desktop PC
- Playing any video games
- You can use a standard 95W CPU in your system
Use Cases
Interesting Facts
It is one of the only 'S' series processors to feature the upgraded HD 3000 graphics.
It was primarily used in the 2011 Apple iMac 21.5-inch models.
Despite having better graphics, it still lacks VT-d (I/O virtualization).
The CPU performance is identical to the i5-2400S, differing only in the GPU silicon.
It was launched specifically to compete with AMD's Llano APUs in the OEM space.
Quick Sync Video on this chip made it incredibly fast at transcoding H.264 video for its time.
It requires a motherboard with video output ports to utilize the HD 3000 graphics.
This CPU is relatively rare on the used market compared to the i5-2400.
It uses the exact same 216 mm² die as the i5-2500, but binned for low power.
The HD 3000 graphics feature 12 Execution Units, double the 6 found on the HD 2000.
People Also Ask
Is Intel HD 3000 good for gaming?
It can play very old games at low settings, but it is not viable for modern gaming.
Can i5-2405S run Windows 11?
No, it does not meet the minimum system requirements.
What is the difference between HD 2000 and HD 3000?
HD 3000 has 12 Execution Units compared to 6 on the HD 2000, making it twice as fast.
Why was the i5-2405S released later than other Sandy Bridge CPUs?
It was a specific SKU requested by OEMs like Apple for all-in-one PCs.
Can I upgrade from i5-2405S to i7-2600S?
Yes, they share the same 65W TDP and socket.
Does i5-2405S support dual-channel memory?
Yes, it fully supports dual-channel DDR3.
What is the CPU mark score for i5-2405S?
Around 1,900 on Passmark.
Is i5-2405S compatible with H61 motherboard?
Yes, but H61 boards usually lack video output ports, defeating the purpose of the HD 3000.
Can i5-2405S run two monitors?
Yes, the HD 3000 graphics support dual independent displays.
Does i5-2405S run hot?
No, the 65W TDP ensures very low heat output.
Frequently Asked Questions
Why does the i5-2405S have a '5' in the name?
The '5' denotes that it features Intel HD 3000 graphics instead of HD 2000.
What is the TDP of the i5-2405S?
65 Watts.
Does the i5-2405S support Hyper-Threading?
No, it has 4 cores and 4 threads.
What is the turbo boost of the i5-2405S?
Up to 3.3 GHz.
Can the i5-2405S output 4K resolution?
No, the HD 3000 is limited to 2560x1600 via DisplayPort.
What is the difference between i5-2405S and i5-2400S?
The i5-2405S has double the graphics execution units (HD 3000 vs HD 2000).
Is the i5-2405S good for video editing?
It can handle basic 1080p editing in older software, but is largely obsolete for this now.
What socket does the i5-2405S use?
LGA 1155.
When was the i5-2405S released?
May 2011.
Does the i5-2405S support Quick Sync Video?
Yes, the HD 3000 graphics include Intel's Quick Sync technology.