Considering a CPU upgrade and would like to hear some opinions -
(best if backuped with facts of course).
 
The choice is between a
2.4ghz/4 core/10M cache
or
2.0ghz/6 core/15M cache
 
All pros and cons considered...
Which would be better? 

Are you modeling nuclear explosions or doing audio?

Really not germane to the question.
So let me give you more detail.

I have a dual LGA 2011 socket motherboard with one CPU.
I decided on the Xeon E5 processor over the i series because
of the difference in FSB in relationship to DMA.

I bought the entry level on this board because of price.
But companies tend to entice you with a base price and bump hard
as you increase components.
So I buy my 'add-ons' through my own sources.

So while I could max out the given specs of two 2.9ghz/8Core/20M cache that is far outside of my budget.
There are several levels in-between though.
And I'm looking at the lower end of those units available

I've presented the two options I'm considering for this.
I could just as simply and for even less money buy a matching CPU/fan
for the other socket (which is a 1.8/4C/10Mc).
It just seems that I should consider uping the ghz and/or cores if I'm already doing this and since it is possible within my range.

Nuclear? Well, it is the 21st century...

And yes, I understand the CPU's need to be matched, That's already part of these considerations. I really don't need an opinion for that option. Just the other two of my original post.

Xeons for any reason are an absolute waste of your money send the baord back and get a refund.

a single 3930K overclocked to 4.5GHz will kill that Xeon until you get into DUAL 3.1GHz.
no reason at all for dual Xeons with audio. maybe just maybe if you are using Vienna's Mir and 3/4 of thier library

benchmarks: 2nd graph down

http://www.adkproaudio.com/benchmarks.cfm

I guess  no one wants to actually address the question in the original post?

I'm not sending the system back.
The Xeon is running smoother and healthier
than any CPU I've had previous.
I find no need to overclock anything.

Too many times, I've read in specs that certain software is optimized for DMA and they refer to the higher grade Mac systems to do that.
Not the consumer Intel systems of PC or Apple.
Xeons are the part that does that.

I don't want to debate the series, especially after jumping into it and finding it the best I've ever had.

The series is irrelevant to the question here.
The question is whether a person thinks the number of cores  or the speed of the chip is more important. And why.

Care to give a view on that? 

edit: Just so you know; your benchmark chart shows the Xeon E5 kills the i7.

a fool and his money are soon parted.

Apple is dead.

as i SAID you need DUAL 3.1GHz to beat the 3930k and if you look at 32 buffer the more than double the cost dual Xeon system barely beats the 3930K

both the processors you mentioned would be dog slow and over priced and vastly outperformed by the 3930K

lets see 3930K $580
single 3.1GHz $2000ish
never mind the motherboard was also double the price
the 3930k tied the single @ 64 buffer 

to answer your question GHZ is almost always better than more cores in most things

Thanks for the ad hominem.

A 3.1 Xeon gives away the fallacy though.
That would be the lower series of Xeon and would be more relative in comparing it to an i3 as far as the levels in each series goes. Perhaps that is why the chart doesn't specify which one?

Just as there are differences in the i3 -i5 -i7,
there are differences in the E -E3 -E5 (&X&W)
So the only comparison in that regards would be to the E5.
And it surpassed the i7 (overclocked?) in all but one test.
and that was with just one Xeon. Wonder how it would stack up to two?

Thanks for your opinion of the original question though.
Care to offer why?

And I do hope others will share ther opinions and why one is better than the other (cores & ghz) here now that we have gained focus.

OH MY dang son not too bright are you.

the 3.1GHz is the FASTEST 8 core dual xeon there is nothing faster made by intel right now. its the E5-2687W $2000 a peice.
so thats 16 cores @ 3.1GHz going against a 6 core system @ 4.5GHz

think that pretty much answers your original question
considering the single 8 core losses to the higher GHz 6 at low latency and 16 core can barely beat it

those little podunk processors you are looking 2.4GHz quad core (E5-2609) and 2GHz 6 core (E5-2620) are going to be dog slow
in fact slower than a socket 1155 3770 @ $290

Quite the name caller  aren't you?

But your interpretation doesn't pan out since the chart shows two 3.1's are slower than one E5 2.7. The only explanation that would leave, is they are a different series.
I'm sure the i series are fine processors. In fact, I'm typing this on an i5.

But I've been running Sonar and Reaper on different systems for the last few weaks and so far this little 'podunk dog' machine has been better than the others.
So, back to the topic perhaps?