What Is More Important?

[OMars]

I know processing is more important, but let's say there is a system with a 32Mhz processor and 128MB RAM would it be equivalant to say, a machine with a 90Mhz processor and 32MB RAM.

P.S. I know what RAM and Mhz stand for, I just want this explained to me. I would prefer it be Epicenter or Radek. But whoever knows this kind of stuff can help me out too.

 

[iignotus]

Processor speed is how fast something can be done, RAM size is how much can be done at one time. There's no equivalency, and that's really all you need to know.

 

[(naw)mcx]

What do you need touse the computer for?

 

[nickspoon]

The first system would be better in one respect (low-cpu, high-mem apps) and the second would be better in another (high-cpu, low-mem). CPU and RAM are incomparable.

 

[Hanz™]

Processor speed is how fast something can be done, RAM size is how much can be done at one time. There's no equivalency, and that's really all you need to know.

for accuracy.

 

[OMars]

Ah, I see now. Thanks people! I love wikipedia don't you?

 

[iignotus]

Ah, I see now. Thanks people! I love wikipedia don't you?

What does wikipedia have to do with any of this...

 

[sam fisher]

Ah, I see now. Thanks people! I love wikipedia don't you?

What does wikipedia have to do with any of this...

He got off his fat, intellectually challenged, arse and did some god damn research?

 

[Epicenter]

To be more accurate (and a bit more complex) RAM size isn't really 'how much can be done at once'. A decent analogy for a CPU would be that it's a person sitting at a desk, doing work. Memory is his desk. If you need him to work on a project involving 128 pieces of paper and his desk size is only able to hold 64 pieces of paper (Imagine the paper as MB of memory) .. he won't have enough room and can't do the work. If you give him too much work to do but it still all fits on his desk, that is a classic case of the CPU being underpowered.

The most important part is that CPU and RAM requirements grow proportionally. If you have a 33 MHz processor, it's probably a 486. Programs back in that day never made use of much more than 1 MB of RAM most of the time, and even the most high-end software didn't need 8MB until you got up to programs that required a 100 MHz 486DX-4, or a Pentium/5x86 generation processor. You couldn't make much use of 128MB of RAM until around the Pentium III/Athlon's hayday. Nowadays, 512 MB of RAM is a minimum, and 1024MB+ is preferred, by software that we normally run on our current class of Athlon 64s, Pentium 4s, and Intel's Core series.

Lacking CPU power will just make things very slow, or completely negate the possibility of running certain programs. Having too little RAM will prevent some programs from running, but others will be content with just using 'virtual memory', or using part of the hard disk as fake memory. It's very, very slow but the program will still run. I would, then, call the CPU the more important factor. But saddled with too little memory, a lot of swapping data to and from the hard disk will make your modern CPU feel like you're plodding through molasses. To use the guy-at-a-desk analogy again it'd be like the papers are all spilling onto the floor, and now it's taking the CPU extra time to dig around on the floor for them, wasting time...

 

[slaanesh]

My favourite analogy of RAM is that to caching.

A computer has various forms of storage as it runs a program. Memory is the storage it uses to hold results of calculations and data.

The fastest memory type are CPU registers; these are used directly by the CPU to store the results of calculations. A register can usually be accessed at the speed of the CPU. ie. a 33Mhz machine could theoretically access a CPU register 33,000,000 times a second.

The next fastest memory is onboard CPU cache memory (which may run at half the speed of register memory), followed by RAM (perhaps running at one quarter the speed) then Hard Drive (or in the case of hand helds like the GP2X, SD memory cards), which really is just another form of memory. Once you get to the Hard Drive, speed of access is dramatically reduced. On a 33Mhz machine you may be lucky to achieve 1,000,000 access per second (for example).

The reason there are various forms of memory is basically economic. A super computer made entirely of CPU register memory would be incredibly fast but also incredibly expensive to make. So, the memory needs to be scaled to make the whole thing viable and we have the configuration commonly seen today.

Having more RAM means that you can hold more data and results of calculations at once though as you can see there are many levels of memory. RAM is the first level of memory that a user can easily change to increase the computer's capability. Registers and CPU cache memory are usually properties of the CPU and cannot be easily changed without changing the CPU itself.

So what's more important? It depends entirely on the application you want to run.

 

[OMars]

My favourite analogy of RAM is that to caching.

A computer has various forms of storage as it runs a program. Memory is the storage it uses to hold results of calculations and data.

The fastest memory type are CPU registers; these are used directly by the CPU to store the results of calculations. A register can usually be accessed at the speed of the CPU. ie. a 33Mhz machine could theoretically access a CPU register 33,000,000 times a second.

The next fastest memory is onboard CPU cache memory (which may run at half the speed of register memory), followed by RAM (perhaps running at one quarter the speed) then Hard Drive (or in the case of hand helds like the GP2X, SD memory cards), which really is just another form of memory. Once you get to the Hard Drive, speed of access is dramatically reduced. On a 33Mhz machine you may be lucky to achieve 1,000,000 access per second (for example).

The reason there are various forms of memory is basically economic. A super computer made entirely of CPU register memory would be incredibly fast but also incredibly expensive to make. So, the memory needs to be scaled to make the whole thing viable and we have the configuration commonly seen today.

Having more RAM means that you can hold more data and results of calculations at once though as you can see there are many levels of memory. RAM is the first level of memory that a user can easily change to increase the computer's capability. Registers and CPU cache memory are usually properties of the CPU and cannot be easily changed without changing the CPU itself.

So what's more important? It depends entirely on the application you want to run.

Let's say a genesis, nes, or gbc emulator. What would be more important? Thanks for the great post, too.

 

[Vimacs]

all of these dont use much ram, where snes would probably the biggest, maybe 12mb with a 8mb rom.

 

[WarmFluffyUK]

Let's say a genesis, nes, or gbc emulator. What would be more important? Thanks for the great post, too.

I'm going to put this as simply as I can:

In the case of an emulator, the CPU speed is very important as the CPU is like the brain of the system. The CPU is what will execute all the commands to run the emulator, and a slow CPU will mean the emulator is slow and jerky.

Most emulators do not make use of things like 3D Accelerated graphics cards as everything is done in software, and that means the CPU does it all. There are however one or two exceptions, the PlayStation emulator on the PC does make use of 3D graphics cards, and because of this the games look better on the emulator than on the original PS1, but this really is an exception to the rule as emulators are inherently CPU intensive.

 

[Epicenter]

Usually in emulation, raw CPU housepower makes the most difference. RAM capacity only becomes a problem in cases where the ROM to emulate is too large to fit in memory, and must be read out from the SD card as emulation is actively occurring. This happens in GnGeo2x sometimes, and you can see a slideshow when it does, because thanks to a massive glitch in the MMSP2 that powers the GP2X, the CPU must stop whatever it is doing and devote nearly all its resources to moving data from SD card to main RAM. If the ROMset is small enough to fit in RAM, this won't happen, as the CPU can access RAM quickly enough to generate 60 frames each second.

This isn't to say the CPU is always the only factor, since you can offload some of the work the CPU must do via 2D or 3D acceleration. Right now, GP2X emulators are often slowed down by slow graphics handling-- for example, the graphics emulation of the SNES is piteously slow for things like transparency because the CPU must handle it all, and it's poorly suited for that task. A dedicated 2D/3D GPU would be able to do that work for the CPU and speed up emulation. The same goes for PSX emulation as WarmFluffyUK mentioned, which dramatically improves performance on systems with slower CPUs but even a low-end GPU available.