Memory upgrade - Technical question.

Question for the PC gurus......

My PC is about 4 years old and hopefully I can get another year or so out of it. It has a 2.4Ghz Pentium4 processor with 512M of DDR SDRAM. I am buying some more memory but want to clarify a couple of things first.

There are 2 memory slots and according to the technical documentation it will take either DDR 266 or DDR 333 memory. The 512MB I already have is DDR 266.

1) Do I need to install exactly the same speed of memory in both slots ?
2) The system bus is running at 532 MHz. So which speed of memory is optimal. If I buy the faster memory will I get the full benefit or will it be restricted by the system bus speed.

Thanks.

1. It is my understanding that you can use different speeds for different sticks of ram, but the motherboard will throttle them all down to match the slowest speed of ram you have installed (so 512 of 266 and 512 of 333 will give you one gig at 266). I've also heard that using different speeds, while technically okay, can cause system stability issues for unknown reasons. The safest bet is to use not just the same speed for each stick, but also the same size and even the same brand if possible.

2. Memory speed is restricted by the system bus speed (and processer FSB speed). A pentium4 2.4g has FSB speed of 533, same as your system bus speed. And since 533 > 333, you will get full benefit from DDR 333.

I'm looking at getting more ram as well, but I'm way more stupid than OP. I just know that the new flight simulator X needs 2gigish to look awesome, and yeah, its that important to me.

A) How do I know what RAM I have in there
B) How do I know what ram I want

When you switch on you box, press the delete key until it jumps into the BIOS setup screen. It will tell you in there what motherboard you have, what memory is installed and how many free slots you have. Be careful not to update anything accidentally.

Once you have the the model number for the mother board, look up the manufacturers website for the documentation. It should tell you exactly what memory you can use.

Instead of searching the motherboard manufacturer's web page, you're better off searching ram maker's sites. You (usually) still need to know what kind of motherboard you have.

www.kingston.com
www.crucial.com (actually has a system scanner on it, might make the whole thing simpler for non-techies)
http://configurator.ocztechnology.co...sp?classid=108
http://www.corsairmemory.com/corsair...or_search.html

I personally would recommend either ocz ram or corsair... they seem to be ahead of the pack in performance and reliability and have been for some time.

Also, from my memory the 266 ram would be better for your system than 333 simply because of the rounded clock speed (i.e. 533 = 266 *2).
Systems *seem* to work better when running with even multipliers like this. Technically the 333 should work faster, but it isn't always so.

Isop

Look for an app called SiSoftSandra and get the free version. Then you can just clicky from your desktop and get all sorts of useful info about what you got. You can run benchmarks too.