Serious Server question logical cores vs physical cores i7

I have a question of some interest, looking for a very professional response, i don't really spend much time with server boards any how.

We have 2 computers

2 x Dual Core Xeons(i7 based)

1 x Quad Core i7


same clock, same cache, same memory used etc.

Which would perform better in a program that makes full use of cores?

Now my guess is the xeon based system, would give some what of a better result, maybe 5% better performance, your using 2 physical cpu's as opposed to having a single die with 4 cores, the 4 cores will be limited to cache since there accessing it on the same die and the 2 cores will have more room since it's 2 cores per die.

The other issue is however what about Latency, now there would be some latency on the serverboard, however i dont think the latency would have that much of a impact, also latency would vary with different types of motherboards and vendors who make it, but i guess going by default standards, i hear xeon processors can communicate to each other also.

If anybody can provide some kind of benchmarks in regards to this, or a wiki in regards to this, any factual information would be great.

 

batter up bump

 

I think it would help if you tell us the actual cpu's in question.

Maybe this can help:

See:
PassMark Intel vs AMD CPU Benchmarks - High End



My bet is that unless you are using a program that is fully optimized for Xeon's, the i7 Quad is the better choice (especially as you can overclock it up to 5GHz+ - depending on the cpu and motherboard you are using).

See:
Asus Maximus IV Extreme-Z Z68 Motherboard Review - eTeknix.com

See:
ASUS Intel Z68 ROG Maximus IV Motherboard Reviews - The ASUS Maximus IV Extreme-Z and Gene-Z Intel Z68 Motherboards - Legit Reviews

 

i'm not talking about overclocking in mind, it's a general question, at the moment i don't have any purchase plans. It's purely based of the given scenario.

 

If this is a purely theoretical discussion then, I would vote for the i7 Quad, then.

Much cheaper, similar if not better performance (as you can see from the PassMark link) and the most up to date hardware/platform choice.

This will only get better (for the quads/hex cores) with the 2011 chipset and the SNB-E chips, although at that point it will be similar (if not more) $$$$.

 

I believe historically, the more closer the cpu are, the better the performance. I believe there was a time when AMD was having TRUE multicore design when Intel was just putting multiple CPU on the same die(which is already better than mulitple physical CPU) and that was also the time Intel was beaten by AMD in the server front(of course there were other factors but this is one of many).


So Quad should be better than 2x CPU

 

Server related questions should be posted on Desktop Review, thanks.