Mixing memories of different frequency- Newbie

[vtv]

Hi

I am part updating my old computer. I have the following now:

Intel 865 GBF moBo
P4 3.0 GHz Prescott 800 FSB

I have two memory sticks of different frequencies with me.

512 Mb 400 Hz DDR (Not sure of the latencies etc. I guess it's a cheapo brand and slow ram)
256 mb 266 Hz DDR (Again cheapo)

The system defaults to 266 Hz. My question is:

1. Is it better to run the system with only 512 Mb at 400 Hz or having 768 mb at 266 hz?

2. Is the performance jump of going to dual channel memory by buying another 512 Mb @ 400 hz significant? I am not asking about performance gain from 256 Mb of additional ram, but from going dual channel.

3. If were to buy another 512 mb Ram @ 400 hz, should I be better of keeping the 256 Mb @ 266 hz idle or is 1280 Mb @ 266 Hz is better?

4. Do high performance memory with lesser latency worth the extra money?

Sorry if I sound lame. I am a total newbie and I am not keen to spend more at this time.

Thanks in advance for all suggestions.

 

[imported_Kensai]

Intel CPUs love bandwidth, dual channel is the *only* way to go if you want performance from an Intel based system.

Again, your DDR266 is killing your RAM speed. Rip it out and get another two sticks of the same type of ram.

Low latencies don't really matter *too* much with Intel CPUs.

 

[vtv]

Kensai..thanks for the quick reply.

So 2 x 512 MB @ 400 hz (Dual Channel) is better than 1280 Mb @ 266 Hz? So I might as well retire my 266 Hz module.

If I have to buy a matching 512 MB stick to get it dual channel, do I have to buy the exact same model as the one I am having or is it enough if I were to match the memory size and frequency?

Thanks again.

 

[imported_Kensai]

2 X 512MB @ 400MHz >> 1280MB @ 266MHz

If you just buy a stick of 512MB it *might* work, though it most likely won't work very well.

You can get a 1GB kit of Corsair VS for ~80$ USD right now.

If you're going with another stick of 512MB, you'll most likely need another stick with the same chips.

 

[stevty2889]

Sometimes dual channel will still work if you get a differant brand, as long as it has the same timings, size and frequency, but it's a much safer bet to get one thats the same as what you already have. And 2x512 @400mhz is definatly much better that 1280mb @266mhz. Using 266mhz with an 800fsb P4 is starving the CPU.