Processor Speed or Ram?

Hi there,

Thanks for all the help in the past.

Question before I buy a new Sony Vaio.


Here are my options


(more Ram, little less CPU)
i7 740QM
8GB
320 HDD 7200 RPM
420M Graphic Card
L3 Cache 6GB

or


(more CPU, little less Ram)
i7 840QM
4GB
320 HDD 7200 RPM
420M Graphic Card
L3 Cache 8GB




Question is -

do I go for Processor (i7 840) speed and 4GB of ram

or

do I go for little less processor(i7 740) speed and go for more ram(8gb)?

Thanks in advance for your expertise/opinion

M

 

Depends on your usage, the passmark cpu score for the 740 is 3626 while the 840 is 3848 so only about 4% faster. That said, it's always easier and cheaper to upgrade memory after market so if you can't decide and don't want regrets later just go with the faster processor.

 

If I have to choose between 4% faster cpu vs. doubling the ram to 8GB. I would definitely go for the ram. You will never notice that small speed difference but , under Windows 7 - 64 bit, you will eventually start to feel a little hemmed in with 4GB.

Andrew makes a good point that later, you can always upgrade the ram, but not the cpu, and if the choices were something like dual core vs. quad core, 2GHz vs 3GHz, massive cache vs tiny cache, or something like that, I would agree that the cpu would be the choice with memory added later.

But for this instance, I would go with the memory.

 

Are you speaking from experience or conjecture?

My PC had 3GB ram on Vista (which I thought was more memory hungry than 7), and I never felt hemmed in. I finally get my hands on my Z Friday and I better not be hemmed in with 4. But it's fine I'll just upgrade if needed.

I too vote for the ram upgrade though OP, if you're looking at premade 1 vs 2.

 

I am speaking from my own experience. Admittedly though, I guess i have always been partial to RAM.

(back when everybody had 128K RAM, I just HAD to have the 320K option )

I find that running virtual machines under Virtual Box, Virtual PC, or VmWare. One definitely appreciates having a little bit of elbow room, in the RAM department. Also, when editing movies or photos...

The reason I mention Windows 7 - 64 bit. Is that the Windows world definitely is more of a memory pig than the Linux world.

2GB in the Linux world is quite a bit.

 

As others here are saying, it all depends on usage, if you have a bunch of applications that are memory hogs (which even FireFox tends to be if you have a lot of tabs open) then certainly extra memory helps. However, if you're highly concerned about multi-tasking and being able to have flawless running HD video while running an anti-virus and whatever else in the background, then a fast CPU can smooth out any issues there.

Frankly I think 8GB of RAM or the 840QM are both almost overkill for a 13" machine and if you go with either upgrade choice you're not going to see a whole lot of upside from a 4GB and a 740QM because that's already amazing. Once you start selecting the highest end components/specs possible the prices go up fast but the performance returns are very marginal.

 

And now that you mention Linux yes actually I did run ubuntu about 80% of the time haha

 

Whenever I am not actually traveling (or surfing while watching TV), which is 90% of the time. My 13" laptop is connected to a 25", 1920x1200 monitor. So, if monitor size is the criteria for memory and speed decisions , and if 4GB and dual core is sufficient for a 13" system , then by that criteria I should be upping it to what? 16GB for my 25" display?

The point is I don't think the display size should be a factor. I would actually be happy to by a quad core, 3GHz, 8GB machine in the 11.1" form factor of my previous Vaio, if such a thing were ever to become available.

Can't argue with that.

 

Nope, my 3gb/Vista was with a 1920x1200 Apple 23"

But yeah if a person is doing multiple VMs and video editing, the more RAM the better. But the way I looked at it when considering my Z12 4gb was that in the future buying 2 new 4gb sticks will be cheaper than initially upgrading my CTO from 4gb to 8gb.. so I didn't see the difference, better to just see if it is enough for me first. I also wasn't gonna half-step with 6 without knowing if it's even overkill, plus even THAT is about the same cost as 2x 4gb replacements.

 

I run Windows 7 x64 with Office 2010 and Firefox every day at work with 1.5 GB RAM, and no problems.

And on my Z, I have 4 GB, which I deliberately chose over 8 GB, because I could get faster 2 GB DIMMs than 4 GB ones, and for my use, RAM speed was more important than memory size.

It all depends on what you use it for.

I agree with those who recommend the faster CPU, simply because there's no way to upgrade the CPU later, but you can upgrade the RAM.

Also, for the slower CPU, with the combination of less secondary cache and more RAM, you are going to get far more cache misses, which slows things down. The difference between the two CPUs get larger as the memory use increases, because the amount of secondary cache relative to the amount of used memory affects speed.

 

And I've heard that humans cannot perceive processor differences of +/-5%, and in addition this is a notebook where a slower processor should lead to slightly longer battery life?

 

Why should it? The faster CPU will finish its work quicker, and be able to spin down to sleep mode more often, which prolongs battery life.

Only if burning both CPUs at 100% for the same amount of time, will the slower one use slightly less power. Otherwise, and that covers almost all usage I can think of, the faster CPU will be more efficient.

 

voltage draw at idle?

are you making an assumption that CPUs only draw power when they're at 100%?