Intel i5 vs. i7 laptop processors

[Bryan Thatcher]

I'm looking at laptops and wanted to know which processor would work best for Revit. The i5 is 2.66GHz w/ 3M cache and the i7 has 1.6GHz w/ 6MB cache. Which is more important, the GHz or the cache size. What else would you consider? Thanks.

[heath.simone]

Depends really what you want the machine to do... Whats your budget?

You know there is also the i7-620m which is 2.8Ghz with turbo boost to 3.33Ghz.

The CPU's shut down cores to boost speed. there are a few websites that have worked out the max speed for different core configurations.

If it was for me i would be looking at how the system overall will suit my needs... Is it going to have usb3 on the i5 system? Whats the graphics card in each machine? Are you going to be doing much rendering? What is the screen resolution is the laptop?

At the moment the two cpu's i would be looking at would be the Intel® Core™ i7-620M Processor (2.66 GHz, 4 MB L3 cache Turbo Boost = 3.33 GHz) and the Intel® Core™ i7-820QM Processor (1.73 GHz, 8 MB L3 cache Turbo boost= 3.06 GHz). The 620 is a dual core chip, and the 820 is a quad core.

How much do you want to future proof yourself, are you going to look at machines that have two hdd bays? etc...

[Bryan Thatcher]

unfortunately i am on a budget. The graphics card and screen are as follows...

ATI Mobility RADEON HD 4670 1GB.

HD DISPLAY Edge-to-Edge FHD Widescreen 15.6 inch WLED LCD (1920X1080) W/2.0 MP

I'll be using it mostly for modeling but I'll also be using it for rendering and presentations. It sounds like I'd be better off with the i7 720MQ. Does anyone have a preference between DELL and HP? Thanks.

[heath.simone]

I would highly recommend choosing the i7-620 over the i7-720 for CAD purposes.

If you go dell or HP you should be able to customize the laptop and choose the cpu you will pay a little bit more but it's a better cpu.

how much are you looking to spend.

[Bryan Thatcher]

$1500.00. I won't be doing much 'CAD' if you mean AutoCAD, just setting up backgrounds and finding information I need for modeling. Mostly Revit, Sketchup and web development. Why are you in favor of the i7-620M, reduced heat? The i7-720QM is a quad core, does Revit take advantage of the 4 processors? I'm leaning towards Dell because on an employee discount and i have already have interest credit there for a year.

[heath.simone]

Most CAD applications (Revit, AutoCAD, etc) do not use multiple cores unless your rendering. So there isn't really any point in having more than 2 cores as it can't utilize them.

If you want the best performance for CAD applications you better off looking at the higher clock speeds of the Dual cores. The Dual core will allow one core to run background applications (email, word, etc) while running the main CAD application on the other.

With the 720 its a notable lower clock speed even when running in dual core mode than the 620. It's not till you get to the high spec 820 that you get comparative CAD performance with 4 cores chips - this would give you an advantage when it comes to rendering and applications that can utilize multi cores.

i7-720QM - Base speed of 1.6GHz - 6MB L3 Cache
Peak Clock Speeds from Turbo Boost
- 4 Cores: 1.73GHz
- 3 Cores: 1.73GHz
- 2 Cores: 2.4GHz
- 1 Core: 2.8GHz

i7-820QM - Base speed of 1.73GHz - 8MB L3 Cache
Peak Clock Speeds from Turbo Boost
- 4 Cores: 2.00GHz
- 3 Cores: 2.00GHz
- 2 Cores: 2.8GHz
- 1 Core: 3.06GHz

This is how the new multi-core cpu's work for clock speed:



If you can get a higher spec dell then go for it.. I personally like the Dell machines, The graphics card you have listed is also more than adequate for Revit/web design work.

[Bryan Thatcher]

heath, thanks for the reply. That was exactly the information I was looking for!

[rbcameron1]

I think heath has it down perfect. With most autodesk products, the bottleneck is how fast your processor is. You can have all the RAM and Quad-cores you want, but if your processor is a dog, it won't matter.

Is there someway to post heath's info in several forum locations? I feel like this is something that should be posted in a lot of discussions....or at the very least a group called, "how to pick out the right computer". Thoughts?

[Taylor1]

Heath,
Im thinking of a Lenovo w510 w/i7-620M, 2x4gb of ram, the FHD display(non-multitoch), and a quadro fx880m card with 1gb of memory. What rae your thoughts on this? Also, a 7200rpm 320gb hard drive.
Thank you very much for your input.