OT: Differences between Intel i7 9xx processors ??

will-3 wrote on 6/8/2010, 4:40 PM
Question:

- With the exception of the i7 980x
- and of the somewhat modest difference in processor speed

Are there any other differences of note between the Intel quad core i7 9xx processors?

Thanks for any info.


(Spce's below for reference:)

Frequencies i7-980X 3.33 GHz
i7-975 3.33 GHz
i7-960 3.20 GHz
i7-950 3.06 GHz
i7-930 2.80 GHz
i7-920 2.66 GHz

Cores 4 cores
6 cores for i7-980X 4 cores

Threads 8 simultaneous threads
12 simultaneous threads for i7-980X

Socket LGA - 1366 socket LGA - 1156 socket

Chipset Intel® X58 Express Chipset Intel® P55 Express Chipset

Memory 3 channel 1066 MHz DDR 3 2 channel 1333 MHz DDR3

Graphics 2x16 PCI Express* (PCI-E*) 1x16, 2x8 PCI-E

Comments

rmack350 wrote on 6/8/2010, 8:29 PM
Speed and price are the only real differences. The Extreme Editions use faster bus interfaces and of course the newer 6 core parts have 2 more cores and more onboard cache.

Maybe I'd be looking for comparisons with Xeons but barring that I'd just go for the part that sells for the right price. They're all quite fast and they all support 24 GB of RAM.

Rob Mack

srode wrote on 6/9/2010, 1:57 AM
I believe the 980 has higher rate quick path to memory as well - more lanes probably so the additional 6 cores can communicate with the RAM more efficiently. The difference in the 4 core chips is the clock speed - which you can achieve overclocking easily and save some money. Extreme editions also have an unlocked multiplier so you can adjust / run higher clock speeds without having to overclock the rest of the machine.
tunesmith1801 wrote on 6/9/2010, 4:27 AM
ram must be installed in 3's
will-3 wrote on 6/9/2010, 6:20 AM
Tunesmith1801...

You said "ram must be installed in 3's"

What does that mean?
TheHappyFriar wrote on 6/9/2010, 7:10 AM
DDR2 requires two identical sticks to get it to work, DDR3 requires 3.
will-3 wrote on 6/9/2010, 7:12 AM
Gee... I should have know that. Thanks :)
kkolbo wrote on 6/9/2010, 7:18 AM

What tunesmith is talking about is that all of the processors listed that use the x58 chipset which I think all of the ones listed are (I do not have a list in front of me) use DDR3 memory. These CPUs have the memory controller in the CPU and it is DDR3. DDR3 uses three channels of memory. That makes the access faster than DDR2 in most cases . Since there are three channels of memory, DIMM sticks work best in groups of three, although you can have just one stick or two sticks, but more than that you have to do groups of three identical sticks.

The other chipset you mentioned supports, I think, the 800 line of Core i7 CPUs which are DDR2.

I am sorry I do not have documentation in front of me and I am not an expert at the latest and greatest CPUs, chipsets, and MoBos. Anyone is invited to correct me. This post input is off the cuff and subject to being completely wrong.
LJA wrote on 6/9/2010, 11:08 AM
I have an i7-860 with 8 GB (4 x 2) DDR3. Works great.
Opticus wrote on 6/9/2010, 1:28 PM
Just started using new computer with i7-930 and 12GB RAM, it's working fine for me, most of my editing is in HDV.
rmack350 wrote on 6/9/2010, 2:04 PM
DDR2 requires two identical sticks to get it to work, DDR3 requires 3.

Not quite. DDR2 and DDR3 don't have any inherent need to be installed in singles, pairs, or triplets. This is determined by the memory controller.

The memory controller for the i7 9xx processors supports triple channel configurations. This means that you can install memory in sets of three DIMMs and get higher throughput than a dual channel setup provides. However, the memory controller also supports dual channel configurations and even unbalanced triple-channel configurations like 1gb+1gb+2gb.

Of course if you're going to the trouble to set up a new PC and buy memory then you should go with a set of three or six matched modules. If you happened to have just two compatible DDR3 modules on hand they'd work, but sets of three are better.

Rob Mack
rmack350 wrote on 6/9/2010, 2:10 PM
You didn't need to know it because it's not true. DDR3 has no requirement to be installed in sets of 3. BUT...systems built for the i7 900 series DO require DDR3 and they DO support triple-channel memory configurations so you SHOULD be buying DDR3 DIMMs in sets of three for use with that CPU series.

Sets of three aren't mandatory but they're a good idea.

Check the motherboard's specs to confirm what you need. There are boards out there that offer odd variations but generally i7 9nn series boards sport 6 memory slots and triple channel configurations.

Rob Mack
rmack350 wrote on 6/9/2010, 2:27 PM
All the i3, i5, and i7 CPUs have on-die memory controllers. They all require DDR3 modules. only the i7 900 series support triple-channel configurations. All the rest support dual-channel configurations.

Rob
will-3 wrote on 6/9/2010, 3:26 PM
Opticus, can you tell us more about your system and the components in it?
Mobo
Video Card
Hard disk (how many, size, speed, etc)

Thanks