Can I get away with i3 rather than i5?

[mel d]

thanks for the link really useful

 

[Atom]

I have just dumped my AMD 550 unlocked to a tri at 3.8ghz. Replaced it with a i5 at stock speeds and the i5 destroys the 550. I do a lot of encoding, etc and it's a breeze now. I haven't started to overclock it yet either..

 

[Rroff]

Bare in mind that clock for clock both the LGA775 quads and the i5/i7 are quicker by a decent margin than the Phenom IIs for encoding. An i5 750 @ 3.4gig will walk all over a Phenom II 965 (3.4gig) and thats an easy to obtain overclock that may not even require increased voltage on the i5. However a respectable setup will cost you best part of £400 - while thats worth it IMO you might wanna wait the extra few minutes on encoding to save money heh.

As to improvements over what you have now... even the i3 530 at stock would absolutely blow it away, per core, clock for clock, the i3 is twice as fast as the old 3gig 800FSB P4 which in turn was around 25% faster than the 2400+... so even not taking hyperthreading into account your looking at performance gains of around 4-5x minimum.

 

[HypnoToad]

Aye, that's right. However, the 32nm process doesn't make the i3 any faster - just cooler and more efficient. Clock-for-clock in single threaded applications the i5 is still faster.

Have a look at this comparison.

nice link thanks. i'm hoping to build a fanless passive machine, as performance isn't my biggest concern so i think i3 is for me. nice to see it's not far off the i5 tho.

 

[cmndr_andi]

Bare in mind that clock for clock both the LGA775 quads and the i5/i7 are quicker by a decent margin than the Phenom IIs for encoding.

Aye, very good point. The X4 955 can generally overclock from 3.2GHz to ~3.9GHz, which is a 22% increase in clockspeed. The i5 can clock reasonably easily from 2.66Ghz stock to 4GHz - which is a 50% increase in clockspeed. So in heavily threaded, CPU dependant apps - a clocked i5 will be MUCH faster than a clocked P2 X4.

However, it is all a function of cost - an i5 sytsem is more expensive and required a graphics card. The performance is there for an i5 system, but you have to be willing to pay for it.

 

[CAT-THE-FIFTH]

Right! It is clear the AMD 955 is about 15%-25% faster encoding than the i3 - and faster at just about everything else as well. The i5 is faster still but not by as much as the AMD is faster than the i3 (if you get my drift!).

I realise I was pricing using the i3 OEM when I should have been using the retail box. So the AMD package is now just short of £300 (using the cheaper 785G mobo suggestion from cmndr andi) whereas the i3 package is £271. Just £29 cheaper.

Hmm... decisions, decisions...

If you are not gaming I would consider an Athlon II X4.

Here is a comparison of the Athlon II X4 630 to the Phenom II X4 955BE:

http://www.anandtech.com/bench/Product/105?vs=88

It is around 10% to 20% slower but this is mostly due to the lower clockspeed of the Athlon II X4.

The 2.8GHZ Athlon II X4 630 is faster than the 2.93GHZ Core i3 530 for video encoding:

http://www.anandtech.com/bench/Product/105?vs=118

The Athlon II X4 630 is £83:

http://www.overclockers.co.uk/showproduct.php?prodid=CP-259-AM

Aye, very good point. The X4 955 can generally overclock from 3.2GHz to ~3.9GHz, which is a 22% increase in clockspeed. The i5 can clock reasonably easily from 2.66Ghz stock to 4GHz - which is a 50% increase in clockspeed. So in heavily threaded, CPU dependant apps - a clocked i5 will be MUCH faster than a clocked P2 X4.

However, it is all a function of cost - an i5 sytsem is more expensive and required a graphics card. The performance is there for an i5 system, but you have to be willing to pay for it.

However the Core i5 750 has risen so much in price that you could end up get a Phenom II X6 1055T system for a similar price and the later would be great for video encoding.

 

[Rroff]

However the Core i5 750 has risen so much in price that you could end up get a Phenom II X6 1055T system for a similar price and the later would be great for video encoding.

That would be an interesting one to compare. From preliminary data it would appear that they can match the i5 for how far you can push the clockspeed on "safe" overclocking settings, while having the extra 2 cores. While they don't seem to be able to keep up at the extreme overclock end - we are talking high end watercooling/LN2 clocks which just don't apply here.

 

[TheLastMan]

[snip] ...the i3 is twice as fast as the old 3gig 800FSB P4 which in turn was around 25% faster than the 2400+... so even not taking hyperthreading into account your looking at performance gains of around 4-5x minimum.

Thanks for that, not wanting to pick holes, but I am not sure your maths works. If the i3 is 200% of the speed of the P4, and the 2400+ is 75% of the P4 then 200/75 = 2.67x not 4-5x

Bearing in mind the 2400+ is clocked at 2gig, I think you probably mean the 3gig P4 was more like 50% faster than the 2400+? In which case the maths is 200/50 which would be 4x faster.

Is there something I have missed?

 

[~>Dg<~]

youve gone too deeeep do you have a pie chart basically it will slaughter your old machine youll sit there and think why havent i upgraded earlier . i had one of those like 6 or 7 yr ago so even the i3 will be like the clouds opening and the sunshine apearing. the quad is the way to go though especially editing , videos and anything similar.

dvd for instance on my old dualcore at 3.0 and my phenom i have now it took 50 minutes for highest quality dvd burn and rip on this 15mins so about four times faster and that was on a reasonable dualcore .

 

[Rroff]

For raw synthetic number crunching performance core for core then i3 530 is approx. 2.67x faster - but then you have to factor in that the i3 has 2 physical cores v the 1 physical core on the 2400+, which puts it theoretically over 5x the performance, add in the hyperthreading that gives you around 30% higher performance on average - tho potentially upto 60-70% in some applications - and your looking at anything upto ~7x the performance. Tho IMO given that applications put different amounts of useage, opptimisations, etc. on the CPU your more likely looking at around 4-5x on average. In short I think any upgrade is likely to blow away the performance you get now.

 

[CAT-THE-FIFTH]

The Athlon II X4 630 is considerably faster than a Core i3 for video encoding and is cheaper too.

Here is a comparison with the Core i3 530:

http://www.anandtech.com/bench/Product/105?vs=118

In the x264 HD Encode tests according to Anandtech the X4 produces 20% to 30% higher framerates than the i3,in the DivX encode it is 2 seconds quicker than the Core i3 and it is 10% faster than the Core i3 in Windows Media Encoder too.On top of this on OcUK the retail Athlon II X4 630 is £21 cheaper too than the retail Core i3 530(the OEM one requires a heatsink):

http://www.overclockers.co.uk/showproduct.php?prodid=CP-259-AM

http://www.overclockers.co.uk/showproduct.php?prodid=CP-311-IN

This is despite the Athlon II X4 630 being clocked 133MHZ lower too. Clock for clock it is a faster processor for video encoding.

It seems that the Athlon II X4 processors can reach 3.5GHZ to 3.6GHZ too:

http://forums.overclockers.co.uk/showthread.php?t=18106677

 

[TheLastMan]

Thanks for all the informative replies. Now keener than ever to do the upgrade if I can get 4 - 5x performance!

Overclocking question (apologies if it is answered elsewhere):

Do I need any special memory to overclock the i3 up to 4GHz?

The anand review says it is possible with stock cooler and stock voltages, but I am concerned that basic memory might not take the overclock.

 

[Redmint]

Get some 1600MHz memory if you want to aim for 4GHz overclocks, 1333MHz RAM sticks might have issues.

 

[subbytna]

in the real world, does spending more money equate to you being able to handle waiting 5-10 more seconds for a task to be done?

 

[TheLastMan]

in the real world, does spending more money equate to you being able to handle waiting 5-10 more seconds for a task to be done?

Exactly my dilemma. I record and encode roughly 5 LPs a week at the moment. That involves WAV -> Flac at 5 minutes a disc and WAV -> MP3 at 7 minutes a disc giving a total of 12 minutes a disc.

By the sound of it I could probably reduce that to around 3 minutes with the i3 or the Athlon II four core (both about the same price).

The i5 package would cost me another £90. I have 500 disks to encode so that is 18p a disc extra cost of the i5 over the i3. How much time saving is worth 18p?

Of course that does not account for any other time savings - such as quicker boot up. But frankly, even with my current ancient setup, I don't have to wait around for most things to happen. Applications load quickly and the only things I have to sit back and wait for are encoding audio files and converting RAW image files to JPEG in Adobe Photoshop or Lightroom.

The main reason for the upgrade is to fix the frequent lock-ups. The time saved on encoding is a bonus - so probably not really worth paying extra for a slightly greater time saving.

 

[Rroff]

between an i3, Athlon II/Phenom 2, i5 you won't really notice any difference in boot times - it will be a difference of like 2 seconds - the biggest change to boot times would be buying an SSD for an OS disc.

 

[TheLastMan]

This is a real budget upgrade, and with 2TB of hard drives on board already it is difficult to justify an SSD.

Now I have a dog slow laptop that could really benifit from an SSD - but that is a different thread.

Thanks for all the help by the way. I think I have made up my mind. Just have to get the cash together now...