512k or 1GHz? Advice please

[Keithchr]

I have 512k RAM at the moment and I am wanting to upgrade to 1GHz

Crucial.Com says this:

512MB — CT6464Z265 DDR PC2100 CL=2.5 NON-ECC UNBUFFERED £29.99 ex. VAT (ea.) £35.24 inc. VAT* (ea.)

1GB — CT12864Z265 DDR PC2100 NON-ECC UNBUFFERED £76.99 ex. VAT (ea.) £90.46 inc. VAT* (ea.)

As you can see: 2x512 would cost £70.48 whereas 1 gig would cost £90.46

Why would I pay more for a single 1Ghz module when 2 512 modules are cheaper? I dont understand this. Also as you can see from the specs below, max frequency is PC2100 so I assume there is nothing to be gained from getting PC2700? Also is it better to fit RAM in pairs i.e 2 x 512 as opposed to I bank with a 1Gig module?

Thanks for your time.

Mobo is ASUS A7M266-M & CPU is AMD Athlon XP2400

Specs are:

184-pin DIMM Banking: 2 (2 banks of 1)
Chipset: AMD 761
DDR SDRAM Frequencies: PC1600 and PC2100
Error Detection Support: Non-ECC only
Graphics Support: AGP 4X
Max Registered DDR SDRAM: 2048MB
Max Unbuffered DDR SDRAM: 2048MB
Module Types Supported: Unbuffered and Registered
Supported DRAM Types: DDR SDRAM only
USB Support: 1.x Compliant

[redwudz]

One reason for using a 1G VS (two) 512Ms is space. If you only had two slots you could put in 2G instead of 1G.(Using 512M) The price is higher because the 1G is more compact.

Many of the memory setups used in newer machines are dual channel capable, where two matched modules can act to increase the overall memory bandwidth, which is a very good thing.

For your setup it would make little difference if they are matched if you don't have dual channel capability. But if you were to decide to buy 2 modules, it would be better if they are matched for future DC use.

I would actually go for DDR3200. The price is about the same nowadays, and you would be able to use it if you upgrade your system in the future. The 3200 will just run at DDR2100 speed if matched with that type of memory. No problem, AFAIK.

[ozymango]

As you can see: 2x512 would cost £70.48 whereas 1 gig would cost £90.46 ...
Why would I pay more for a single 1Ghz module when 2 512 modules are cheaper? I dont understand this.

EDIT: I started writing the following before redwudz replied so much of the following is pretty much just a long way of saying what he did. Darn! But being I already typed it, what the heck. :P

There are some technical reasons for it being more expensive to squeeze more RAM on a single DIMM or SIMM, but in layman's terms it's usually simply just a matter of the max amount of RAM your system can take, and how many slots you've got to work with.

There are some really nice motherboards out there that only have 2 slots for RAM, so if you wanted "only" 1gb of total RAM -- you can either run 2 512mb DIMMs or a single 1gb DIMM. But say you only have two slots and you want to run 2gb of RAM and you've got 2 512mb DIMMs already taking up both slots? That's why you have to pay more for more RAM on a single DIMM, you can't just keep adding more DIMMS.

And depending on your system, you may have to buy smaller (memory size) SIMMs or DIMMs because your system is configured to only accept certain combinations. I've got a friend with an old Gateway Solo laptop, and she wanted to put in more memory. So how much could she get, she asks me? I check the specs, and that laptop has 2 available slots, with a maximum RAM capacity of 256mb.

But wait! Reading further, each RAM slot would only accept up to 128mb of RAM, so though there are 256mb SIMMs that would physically fit in those slots, she couldn't get away with buying one single (cheaper) 256mb SO-DIMMs, she had to pay a bit more for the two 128mb SO-DIMMs.

So installing RAM can be a bit of a black art ... ... my own home system has 4 memory slots, and each slot can run a max of 256mb of PC133-SDRAM. So there are 512mb DIMMs that'll physically fit my PC, but I can't use them, so my max RAM is 1gb, in 4 256mb DIMMS. Actually I "only" have 512mb, running one 256mb DIMM and 2 128mb DIMMs (the last two "smaller" dimms I happend to pick up dirt cheap from a friend whose new system uses DDR RAM and couldn't use the 128mb SDRAM).

See, it's really very simple!

P.S. And for any computer guys or gals out there who see me throwing out DIMM and SIMM and SO-DIMM and notice I probably used the wrong term in several places, yeah, yeah, I know, I never can remember unless I'm actually looking at the chip!

[EddyH]

i wish installing memory would be as easy as it used to be......... you know....... buy SIMMs, click them in place, remove old ones if neccessary, close lid and forget

it's been nothing but trouble the last couple times I've upgraded, and it's always infuriating, infathomable things where all you can do is return (or RMA) the stuff and have it replaced or substituted - and likely incurr a restocking fee if you ordered online.

[pfh]

it's been nothing but trouble the last couple times I've upgraded, and it's always infuriating, infathomable things where all you can do is return (or RMA) the stuff and have it replaced or substituted - and likely incurr a restocking fee if you ordered online.

Just use the memory selectors from the mem. manufacturers web site- unless you'er buying "no-name" stuff.

[ozymango]

i wish installing memory would be as easy as it used to be......... you know....... buy SIMMs, click them in place, remove old ones if neccessary, close lid and forget

Yup yup yup. Although I do remember my very first computer was this Tandy Radio Shack POS (not a TRaSh 80 but some DOS beast) and I distinctl remember having to put in these little 8-pin chips that were a royal pain, I kept bending the little pins. :P

I'm lucky in that I work for a university (computer tech.) and we've got various stacks of memory chips we can test systems with, upgrade, whatever, and I don't know how your average computer person without a big stack of RAM sticks to play with can possibly keep a computer running anymore -- we get some weird computer problem, we can swap out RAM, swap out disks, CPUs, whatever, and if we had to send things back and wait for an RMA before trying the next thing ... we'd never get anything done!

My "favorite" is when you get RAM that's only slightly bad, so when you're building a computer Windows will crash somewhere on the install and fortunately somebody else looks over your shoulder and goes, "Oh, yeah, that's a classic sign of bad RAM" so you swap it out and voila, it's all working again. Try that at home!