CPU Comparison
Core i7-820QM vs Core i7-840QM
A side-by-side comparison of specs, performance and value. The Intel Core i7-820QM is a high-end mobile quad-core processor launched in September 2009. Based on the Clarksfield architecture, it features 4 cores and 8 threads with a base clock of 1.73 GHz and a turbo boost up to 3.06 GHz. With a 45W TDP, it was a premium offering for early gaming and workstation laptops. Built on a 45nm process, it includes 8MB of L3 cache and supports dual-channel DDR3-1333 memory, but lacks integrated graphics.
The Bottom Line
Overview & Launch
Specifications Compared
Performance Compared
Productivity
8MB cache and 8 threads help with heavy multitasking.
8 threads and 8MB cache help with heavy multitasking.
Gaming
Good for 2009 games but lacks single-core speed for modern titles.
Good for 2010 games but low single-core by modern standards.
Virtualization
Excellent for legacy VMs.
Excellent for legacy VMs with VT-d support.
Efficiency
45W TDP on 45nm is very hot and inefficient.
45W TDP on 45nm is very hot and power-hungry.
Specialized Performance
AI / ML
- No AI hardware
- No AI hardware
Content Creation
Gaming
- Requires discrete GPU
- Can bottleneck modern games
- Good for retro gaming
- Requires discrete GPU
- Can bottleneck modern games
- Good for retro gaming
Industry Impact
Best CPU by Use Case
Target Audience
Strengths & Weaknesses
Pros
- Large 8MB L3 cache
- High 3.06 GHz turbo boost
- 8 threads for multitasking
- Socketed (Socket G1)
Cons
- Very hot running (45W)
- No integrated graphics
- Obsolete 45nm process
- Expensive at launch
Pros
- Large 8MB L3 cache
- High 3.2 GHz turbo boost
- 8 threads for multitasking
- Socketed (Socket G1)
Cons
- Very hot running (45W)
- No integrated graphics
- Obsolete 45nm process
- Expensive at launch
Competitors & Alternatives
Our Verdict on Each
A groundbreaking mobile CPU in 2009 that brought 8MB of cache and 8 threads to laptops, but heavily outdated and power-hungry today.
Best for: Repairing a legacy mobile workstation
Read the full reviewA top-tier mobile CPU in 2010, offering excellent multi-threaded performance and a large cache, but runs hot and is obsolete today.
Best for: Repairing a legacy mobile workstation
Read the full reviewFrequently Asked Questions
Which is better, Core i7-820QM or Core i7-840QM?
Based on our editorial ratings, the Core i7-840QM comes out ahead with a score of 6.5/10. That said, the best choice depends on your workload — check the spec and performance breakdown above for gaming, productivity and efficiency differences.
Which is faster for gaming, Core i7-820QM or Core i7-840QM?
For gaming, the Core i7-840QM leads with a gaming performance score of 35/100 among Core i7-820QM and Core i7-840QM.
Do Core i7-820QM and Core i7-840QM use the same socket?
Yes — all of these CPUs use the Intel Socket G1 socket, so they share compatible motherboards.