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I7 versus 2 year old e6400

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February 16, 2009 3:40:47 AM

Here's the deal, I've got a 2 year old e6400 that runs at 3200 mhz, with DDR2 800 times at 4,4,4, 12.

So, after 2 years, one would think that it would be time to upgrade. But I can't seem to find information comparing the performance per CPU core of the new i7 chips versus my own. Assume I get the $285 i7 from newegg, the Intel Core i7 920 Nehalem at 2.83 GHZ, and I manage to overclock to 3.2.

Yes, I know that it has double the CPU cores, so don't give me some synthetic benchmark that uses all 4 cores. I'm looking for a more realistic comparison, since most software I use day to day will not benefit from multi-core.

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February 16, 2009 3:47:48 AM

Ok, I just looked further. I found a benchmark site saying that the i7 was "16% faster, clock for clock, then the Core 2".

Now, I've got an older model Core 2, so maybe that's a little pessimistic. Let's say the i7 is 25% faster, clock for clock.

Hmm...in order to justify spending $1000 on an upgrade, I need at least a 50% performance boost, don't you think?

To get that, I'd need to overclock to 3.8 GHZ...not doable without special cooling.

Darn, I guess I'll be using this obsolete clunker for a while
February 16, 2009 4:28:40 AM

The whole point of i7 is really that it can run eight threads with decent performance on four cores, with various small optimisations that give some improvements in IPC, particularly in 64-bit code. So if you only need to run two 32-bit threads, then there's really no point in upgrading... you're not likely to see any huge improvements in IPC or clock speeds any time soon from Intel or AMD, the future is largely going to be improved multithreading.
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February 16, 2009 5:04:20 AM

Well Habeeb to make things clear, the i7 is 16% faster than a Q9550 quad and not just any other Core2...And frm that it implies that the i7 will easily be 50% or even mayb more faster than ur current CPU...
Please do go through the full articles here in the TH website...it will give u a much clear view....
And certainly MarkG's comments do make sense...so google around and make the decision...
February 16, 2009 5:21:12 AM

I just found the CPU charts. Here's how I'm looking at them : I take the e6400 benchmark score, and I multiply or divide by 1.5, since my machine is a 50% overclock.

I then compare that to the i7 at 3.2 ghz.

So, for the MP3 encode benchmark, an i7 would be 10% faster.

Definitely not worth spending a grand.

For 3d mark and for Winrar and other multicore apps, there's a huge performance difference, but I don't use multicore stuff very much at the moment.

It looks like I'll need to wait at least another year, for higher clocked i7 or i5 parts. I need to wait til the prices on a 3.6 ghz (stock) i7 chip reach affordable levels. (and since there is not a 3.6 even available yet, and the 3.2 costs $1000, a year at minimum)

Bummer, I was looking forward to snappy new hardware.
February 16, 2009 6:37:18 AM

I agree with your assessment. You picked your hardware well and it's still very serviceable. Even if the i7 CPU+platform was say 50% faster in some circumstances, doesn't mean 50% better computer experience since there is other component bottlenecks like HDD, VID, I/O subsystem, software not written to take advantage of 4 cores, etc.

I upgraded from a single core to a quad core, 2 generation jump in video card and doubled my ram, the only thing that I can really notice is outlook opens almost instantly and before it took about 10 seconds. Guess I have to go buy GTA4 to make me feel I dropped big coin for a reason :na: 

February 16, 2009 7:11:33 AM

Thanks for the compliment. I suppose a 50% overclock is a pretty huge boost, really. Not that I'm bragging, I just got lucky and got a CPU that could handle it, and put a decent cooler on it. (thermaltake Big Typhoon, and eventually I lapped the heatsink)

And I know I need an SSD to lift the hard disk bottleneck. Even my current system would probably feel a lot faster with an X-25E as the primary system disk.

But I was looking at the benchmarks for how much an SSD, or even a RAMdisk helps, and it struck me that for many, many things the CPU is the ultimate bottleneck. Part of the reason, say, internet exploiter takes a few seconds to load is that you don't have enough CPU performance per core to make it happen instantly.

The machine is a dual monitor workstation, with 2 massive 27" displays. I'd love to be able to upgrade the internals to make it really feel like a professional workstation, with instantaneous responses to virtually anything. I'd eventually want probably an i7 overclocked to 4 ghz, 12 gigs of RAM, and 2 X-25Es in RAID 0.

Oh, and while I'm throwing money around, might as well invest in good enough cooling to make it totally silent. Basically a $250 fanless water cooling kit combined with a fanless ($120) power supply and a fanless dual head video card.
February 16, 2009 8:32:23 AM

Get a 920 and overclock it with a high end water cooling system, you should be ok as long as you don't get a thermaltake system.

You'll be able to get past 965 performance for cheaper, a lot cheaper.
February 16, 2009 9:00:47 AM

Helloworld : do I really need water cooling? Or would a really good conventional heatsink work? The reason I ask is that a high end water system is $300, and it's not going to get any colder than maybe 5-10 C over ambient.

February 16, 2009 7:11:54 PM

Well, I'm an incredibly impatient person. As far as I'm concerned, any delay detracts from my enjoyment or productivity. But, for it to be worth paying for a whole new tower (might as well replace the whole box and use the old one elsewhere), I need to get a large enough performance boost that these little delays are actually significantly shorter.
February 17, 2009 1:31:53 AM

jimbo : but even at 3.8ghz, are we talking a significant speed up in per core performance? I think the Phenom II is about the same IPC as my aging e6400, and 3.8 ghz then would be an 18% performance boost.

That 18% needs to be at least 50% before it's worth buying all new parts.
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February 17, 2009 8:24:39 AM

A phenom II is definitely not worth it - especially when you already have a 775 motherboard.
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February 17, 2009 11:07:27 AM

^ Agreed, the gain isn't enough to justify the upgrade cost. Try again a few generations later ;) .
February 18, 2009 1:39:12 AM

Thanks for the suggestions.

I'm thinking that if I upgrade, I might as well change out every part. That way I would have a complete PC to hand down to my family members. So, replacing the whole box doesn't make any sense for only a 25% boost. Especially when an OC to 4.0 ghz might not be stable long term, or there could be motherboard chipset problems. My current system is stable, and has been working for 2 years now, with a 50% overclock.

So I was going to buy an i7, and put in an X-25E SSD, a fanless VGA card (this system's not for games), a new case with quieter fans, new power supply, heatsink, sound card, ect.

But 25% is barely enough CPU to even notice. When one of my bloated productivity apps decides to hog a CPU core while it thinks for a few seconds, it will still noticeably lag.

After this discussion, I've decide to postpone my upgrade until at least next Christmas. Maybe, by then, Intel will have released an i7 that can be overclocked to at least 4 ghz at a reasonable price. ($300 is reasonable, $1000 just for the chip isn't)
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February 18, 2009 2:28:36 AM

Quote:
A 720 BE OC'd to 4ghz will probably give 25% gain over an E6400 for about $175 or so (including a cheapish mobo). In a years time that 50% he is looking at will probably be possible with a chip upgrade alone, costing another $125.

That's not much more than a single i7 (not including the mobo and DDR3) would cost right now. I'd take 25% better performance now and 25% later at a lower cost, at these prices it's just too good to miss but only the OP will know for sure if it's right for him.


The next AMD platform isn't Am3, right? PhII is supposed to be a dead end, right?
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February 18, 2009 5:35:52 PM

Quote:
You could get a 720 X3 BE and a mobo for about the same cost as a E8400 or E8500, and the X3 is a better chip in most benchmarks. It's most definitely worth looking at.

It might not give another 50% performance increase like the OP wants, however he's not going to get 50% extra performance on a 775 mobo anyway.



About the same price? The 720BE is $169 at newegg. The e8400 is $164. I'm not saying the OP should uprgade to either chip but what you said is simply not true. A 720BE plus lets say a 100 dollar board would be $269. Thats $10 less then a Q9950.


The 720BE is a great chip and it does make more sense to build a new system with it over the Intel dual cores. But to switch from socket 775 core2 build to it is just foolish and a waste of money.
February 18, 2009 6:25:00 PM

Thanks, someguy7.

Although, still...bummer. I'm just not used to this new reality, whereas 2 years passes and there isn't something a ton faster available. CPU power has been doubling every 18 months for 20 years now, and suddenly it is no longer effectively doing that.

Yes, if you factor in the fact that the i7 can do 8 threads at once at about the same speed my e6400 can do just 2, that's a 4 fold boost in speed. About what you'd expect after 2 years. But in practice, running adobe acrobat or windows or a web browser : none of these applications use more than one core at a time, and so when they take a moment to do something, an i7 wouldn't make that annoying moment any shorter.
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February 18, 2009 6:49:47 PM

The cpus have got faster. Just what you are referring to isnt dependant on cpu power.
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February 18, 2009 8:48:13 PM

Its still not worth it and its no brainer not to switch period. The OP doesnt use software that uses more than 2 cores.

The DDR3 board support means nothing. The performance increase going to dd3 over ddr2 is next to nothing. Just as going to DDR2 from DDR was. Ram is just hype for almost everything anything. The amount of ram and the ram timings are what makes a difference. Not single/dual/tripple channel nonsense. Thats what great about AMD this time around. You're not forced to buy a am3 board and the ram. The learned from the socket 939 crap I suppose.

The peformance increase from a 3.2ghz core2 to whatever the end overclock of the AMD cpu would be is just not worth it in my opinion this case.

I find it hard to not recommend the 720BE right now but for this case I just dont see a reason to switch/upgrade the ops system. He is looking for a huge improvement for his money which he wouldnt get.
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