RAM upgrade compared to CPU upgrade?

Question

Hi, I am currently considering upgrading my laptop memory and maybe getting a faster hard drive. Obviously with it being a laptop I cannot upgrade the CPU. I was just wondering is there a comparison that would show how much quicker it will run with more RAM compared with upgrading the CPU, for example:

Upgrading by 512MB is roughly equivalent to upgrading a CPU by xxxx MHz

Thank You.
Gareth.

Answer 1

That’s a difficult question to answer. Upgrading RAM will allow you to put more things in memory and avoid the delay of retrieving the data from the hard disk.

If you have a 500MHz processor it will always be 500MHz no matter what the size of your RAM. The amount of instructions your computer can complete per second will remain unchanged.

Think of the following analogous question:

I have a Ford Pinto with 100 horse power. If I start using 7th street instead of 8th street because it has less traffic lights, what equivalent horse power would my Ford Pinto have?

The answer, of course, is that the horse power (relative or not) of your Ford Pinto will be the same.

Yes, you will arrive at your destination faster using 7th street. So you could theoretically calculate the accelerations/speeds of different horse powers and compare those to the time it takes you to arrive at your destination depending on the street you use. But the comparison would be irrelevant. “Apples to oranges”.

Answer 2

To say you can not compare them at all is not strictly true, you can not give direct comparison ok, but you can put it in to context...although you will need to do some serious resource monitoring to really gauge how much of a benefit any upgrade would give you.

For example upgrading the RAM when you are not fully maximising what you have already will see little to no benefit. Whereas, if you monitor page file usage / page faults and notice a constant heavy trend occuring (i.e. many page faults), more RAM will help. (A page fault, in over simplified terms, is when a program looks in memory for a program but it's not there so it fetches it from disk).

Disk replacement will only help if you are using disk instensive applications. This can be misleading though, dont assume that just because you machine accesses the disk a lot that its because the application requires it. You page file is also on the disk so your first check your RAM as above to make sure this is not causing excessive disk usage.

Final point, disk swaps on a laptop are quite usually a pain in the @ss. Unless you have two 2.5" HD drive bays and a copy Ghost.

Anyway, first thing to check with regards to the RAM upgrade:

run perfmon (Start->Run-> perfmon (and click ok) )
on the system monitor add a counter (click the + button above the graph)
Select the Memory category and add Page Faults/sec from the list.
Ok everything untill you get back to the graph, it should now be counting. Now is the tricky part, you need to try guage when there is a problem, to do this open a few programs, maybe just one or two more than you would normally have (like maybe 3 or 4 internet explorers, outlook, word, excel) let the system idle, that is wait until absolutely everything has finished loading completely. That does not mean when they show on the screen, that means when your disk stops going so crazy! Your page faults graph will most likely spike and max out whilst loading everything dont worry this is fine.

Once everything is sitting open you want to start watching the graph again, maybe move back and forth a bit between windows or type a url into one of the IE windows. Remember, the graph will spike, that is normal but you need to look more for a baseline average here. For example if the graph is consistently running above say 16 (using the 0-100 scale at the side) then I would say you could benefit from more RAM.

This again is a bit vague, some people say as low as 5 others say its not a problem till you are over 40 but from my experience 16 - 20 seems about right.

To bring this all to a conclusion, how does this help the CPU? (Again this is vastly over simplified) Well, every time a page fault occurs the memory subsys must go interupt the processor, go fetch the necessary data from disk and load it in to memory. This takes CPU cycles. So by adding more RAM your computer does not need to pull in data from disk so much and therefore does not bother the CPU as much.

Answer 3

it depends on the kind of OS you use for instance you must have at least 256 ram for XP,to have good performance install 1G ram if you are using graphics or play games,cpu can't be changed to faster,faster HD can help in scan or search process.

Answer 4

you can't compare in that way,Because RAM and CPU doing 2 things.
but you can gain much perfomence by upgrading RAM

Answer 5

They cant be compared

Answer 6

im sorry, im not sure what this means. but i always go onto google when im stuck, hope this helps. x