Help me decide on a CPU

[Anonymous]

I am in the process of building a new PC and I am at a fork in the road deciding which CPU I want to use.

I could go with the:

 AMD FX-8350 (good for another two years with AMD architecture)

• Vishera Architecture
• 8 Core
• 4.0 Ghz
• 4 x 2MB L2 Cache
• 8 MB L3 Cache

Intel Core i7-4790K (end of the line for this socket size, and DDR3 memory for Intel)

• Haswell Architecture
• 4 Core
• 4.0 Ghz
• 4 x 256 kb L2 Cache
• 8 MB L3 Cache

Intel Core i7-5960X (start of the DDR4 era, very upgradeable in the future)

• Haswell-E Architecture
• 8 Core
• 3.0 Ghz
• 8 x 256 KB L2 Cache
• 20 MB L3 Cache
• (if the cache is not that important, I could drop to 15 MB of L3 cache and go with a faster clockspeed on this chip)

Do we know how important L2 and L3 cache are vs clock speed for tasks like:

• Opening drop down menus in the ribbon?
• Ribbon expanding its context based on the object I have picked?
• Using floating windows that pop up based on context?
• Rotating in 3D? (there is always a lag to get into 3D)?
• Panning around in very large drawings?
• Arraying large blocks?
• The deadly hatch that never ends?
• And the occasional rendering of a building?

I know that there is a big difference between using an Nvidia GPU vs ATI GPU. Does that same difference in architecture extend to AMD architecture and Intel architecture?

Why does Intel only go with 256 KB for each core of L2 cache? Wouldnt that register more L2 cache misses and push it off to L3 cache? It sounds like AMD would win in that department with 2MB of shared L2 cache before I have to goto the 8MB L3 cache.

[Anonymous]

Unless there has been a recent change in AutoCAD's use of processors, which I sorely doubt, you'll be looking for a CPU which has the highest Single Threaded Performance. The i7-4790K is currently topping the charts. There are no figures yet for the newer LGA2011v3 socket CPU's, i'm interested in the figures for the E5-2637V3, this CPU will have ECC RAM support which maybe worth something considering how many times AutoCAD crashes.

Here is a chart worth considering:
https://www.cpubenchmark.net/singleThread.html

[braudpat]

Hello from France

Sorry for my US/English which is not very fluent ...

The right choice (for me) is of course the Core i7 4790K which is the fastest available CPU for ACAD, Revit, Inventor, etc (Even for SolidWorks) ... And it is cheap !!

... A Quad-Core is ENOUGH ! ... Except if you plan many renderings, videos, etc (with 3DSMax and others specific Software) ... In THIS case, you can eventually consider a Six-Cores !?

Basic Speed = 4.0-4.4 Ghz but with a good ventirad (High End Noctua for example), you can run at about 4.4-4.6 Ghz (+400 Mhz with TurboMode)

Support for fast DDR3 is enough - DDR4 is not (for me) a very important point !

With a good PC Cabinet and a good Power Supply

With 32 Gb (4x8 Gb) of DDR3 1866 Mhz

With a NVidia GTX 780 TI (3 Gb)

With a fast SSD + a fast SATA (7200 rnd/mn)

The cache size is not (for me) a main priority !

ECC memory is not necessary, if you buy high quality Ram ...

I advice you to buy a FAST Core i7 and not a superb and expensive (Dell, HP, Lenovo) Workstation with Xeons ... Wharf, Wharf ... And I am Engineer certified on xxxx Workstation ...

So it's your choice !?

[braudpat]

Hello from France

If you look at this french Topic/Subject and especially the latest messages, you will see somebody very satisfied by its new PC (Core i7 4790K overclocked) !

http://forums.autodesk.com/t5/autocad-francais/recommandations-hardware-pour-gros-projets-autodesk/m...

NOW >>>

Core i7 4790K overcloked at 4.4 Ghz (Water Cooling : Coler Seidon 120M) - Asus Z87-Pro - 32 Gb Ram DDR3 1600 - GTX 780 TI (3 Gb Ram) - SS Samsung 840Pro  250 Gb 

Before >>>

WorkStation HP Z420 - Intel Xeon E5-1650 12M 1600 6C CPU - 16 Gb DDR3 1600 ECC - NVIDIA Quadro K4000 3 Gb GFX - 256 Gb SATA 1st SSD

Rapid translation (waiting for more complete tests) :

1) Opening a large Inventor 2014 project : 2 mn --> 20 secs

2) 3D to 2D : before many hours , now 15 mn

Waiting for more complete tests and others tests with ACAD Plant 2014 ...