No problem

Looking back at my posts, I see that I haven't been particularly clear and explained the relationship between CPU, system bus and RAM clearly enough - I'll do it below, although it's a bit of a "wall-of-text", which is often not the best way :

There are five main parts to a computer - you've probably heard them before - CPU, Sytem Memory (RAM), Motherboard (including the chipset), Graphics Adapter and Mass Storage (HDDs).

The parts that we are interested in right now are CPU, motherboard, and RAM. The three need to be able to communicate with each other, and need to be able to synchronise when data is transferred - for all the electronic wizardry that goes into a modern computer, it still effectively runs on clockwork

The part of the computer that is primarily responsible for the synchronisation of the CPU and RAM is the system bus. The system bus is one half of the mechanism that controls CPU frequency, and one half of the mechanism that controls the RAM frequency. The system bus itself operates at certain frequencies. It is the frequencies that determine how much data can be sent back and forth between components. Higher frequencies represent higher speeds (also referred to as bandwidth).

The system bus on somewhat older computers like yours and mine runs between 100MHz and 200MHz. This is blazing fast compared to PCs from 10 years ago, but is nothing like the speeds that your processor can reach - your current CPU is running at 2.4GHz - 2,400MHz. CPUs can do this because they have a multiplier. As an analogy, imagine that your PC is a bicycle. The system bus is similar, in a way, to your legs as you pedal. you can only complete so many pushes on the pedal in one minute. Some bicycles are much faster than others. This is not because some bicycles allow you to pedal faster, but rather because some bicycles have gears, which multiply the number of times the wheels rotate in relation to your pedalling. The gears are acting as a multiplier, in a similar way to the CPU multiplier in a PC. Obviously, it's not an exact analogy, but it illustrates the relationship between system bus speed and CPU speed.

If you go back to the screenshots you posted, you'll notice that, on the first shot, there is a box just over halfway down the window. It states that your processor speed is 2,390MHz - 2.4GHz. If you look below that, you'll notice that it states you have an x18 multiplier in effect, on a system bus speed of 132.8MHz ===> 132.8 x 18 = 2390

• system bus = 133MHz
• multiplier = x18
• CPU speed = 2390MHz (2.39GHz)

Thus you can see how the system bus helps to determine CPU speed.

Now, your CPU needs somewhere to store the results of all those calculations it does (2.4GHz = 2,400,000,000 calculations/second). The first place for this is the RAM. The RAM is similar to what psychologists call "working memory" in humans - it is where data is stored temporarily while the CPU does something else. Imagine, for example, that you want to do the following calculation:Your computer can't do the calculation all at once, it breaks it down into stages, does them one-by-one, and stores each result in RAM until it is ready to do the final calculation:

• 12 x 12 = 144
• 2 x 24 = 48
• 144 / 48 = 3

It will then display the result.

The benefit of storing data in RAM as opposed to on a hard disk is that it's available immediately. We'll come back to this later.

The RAM doesn't connect directly to the CPU, but goes through the system bus, and works on similar frequencies (i.e. there's no multiplier capable of the same thing as a CPU multiplier). The frequencies are not always the same, particularly if you're overclocking, but they're mainly governed by the system bus frequency. Therefore, on a standard setup, the RAM data transfer frequency (remember "bandwidth") is the same as the system bus frequency. In your machine's case, this means that your RAM is running at 132.8MHz, or 132.8 Million input/output cycles per second.

Modern RAM is known as DDR (SD)RAM - the "DDR" stands for Double Data Rate. Essentially, this means that your RAM can input/output at double the system bus speeds. Therefore a system bus speed of 133MHz will often be called DDR266 (133 x 2 = 266). DDR RAM mostly comes in DDR266, DDR333, and DDR400 flavours, each designed to work with a particular system bus speed. RAM designed to work with a system bus speed of 200MHz (DDR400) will work fine with lower system bus speeds, hence your PC works fine.

DDR speeds are also referrred to as "PCxxxx" This is just another way of expressing the same information. The number on PCxxxx RAM is simply a multiple of the system bus speed. For example, on a system bus running at 133MHz, the DDR speed is 266. (133 x 2). Now, the PCxxxx speed is 2100 - 133 x 2 x 8. Thus, DDR266 RAM is also referred to as PC2100.

For a system bus speed of 166MHz, the matching RAM speed is PC2700:

• 166 x 2 = 333
• 333 x 8 = 2656

The discrepancies come from rounding the results to nice, round, memorable, human-friendly numbers.

If you look at the "Memory" tabs in the CPUz screenies you posted, you'll notice that it says "PC3200". This is the same figure that the Kingston memory checker gave you. 3200/8 = DDR400. 400/2 = 200. This shows that the RAM was designed to run on a system bus of 200MHz. However, it is, in fact, running at PC2100, since your system bus is running at 133MHz. The maximum speed your system bus can run at is 166MHz, resulting in memory frequencies of DDR333, or PC2700. This is why I said there's no point in buying PC3200, as you're just wasting money on RAM your system can't take full advantage of.

OK, moving from 256MB, or even 512MB to 1GB makes a very noticeable difference to your computing experience. I mentioned earlier that writing data to RAM is better than writing data to disc because it's much more responsive. Basically. PC2700 RAM has a data transfer speed of 2.7GB/Second. The newest hard drives can read/write at 300MB/second theoretically, and in reality somewhat slower than that. RAM speeds are at least an order of magnitude faster than hard drive read/write speeds. Thus, when your system runs out of RAM to store data in, it is forced to write excess data to the hard disk. this operation, called "paging" is cripplingly slow. This is why increasing RAM often increases the performance of the system, particularly on machines with little RAM.

My current laptop came with 256MB RAM and a 1.4GHz processor. Replacing that with 1GB of RAM really made the machine more responsive and fluid. However, there is a limit to the difference that RAM can make. If an operating system and any running programs are not occupying more RAM than is available, then the system won't have to write data to hard disk, and consequently there will be little to no noticeable lag. In day-to-day operations , lag will much more likely be caused by:

• A slow processor
• A slow hard drive
• A heavily fragmented hard drive
• An old video card (in games and/or 3D applications)
• Too many processes eating processor cycles
• Spyware/Adware/Trojans (see the previous point)

.A full install of XP Pro, with anti-virus and anti-malware running should take up around 300MB RAM after a full day's use. This leaves 700MB for programs to load into. In day-to-day usage, you will never find programs using >700MB RAM. The only real exception would be gaming. Battlefield 2, for example, likes to sit in memory. It has a fat arse, however, and takes up more than 800MB if your system has the RAM to handle it.

Where or when do you notice slowdowns? If it's gaming, I'd suggest that an FX5500 is nowhere near capable of running modern games - it would even struggle with GTA: San Andreas - I know, I used to have one

the setup you have isn't harming your computer in any way whatsoever, IMO - it works, doesn't it?

Any advice I gave you would depend on what you want to do with your computer, so... What do you want to do with it? Be warned, i might say "buy a new computer"