Komodo

Can I mix RAM that has different speeds and timings?
what would be the faster setup for 2 gigs of ram? 4x512 2x1024 or 1x 2048


I tried google but it got me nowhere, thanks in advance for the help

Soulstorm

In the first question, I would say that it is possible, though not recommended. In the second one, I am not sure.

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Booooze

I'm not to sure which would be the fastest setup (4x512 2x1024 or 1x 2048). Truthfully I don't think it really matters. If it does, the difference will probably be in like nanoseconds. Not enough for you to really notice. What counts is how much you have (MB, GB), and at what speed it actually operates at (133Mhz, 333Mhz, 533Mhz, 800Mhz, etc).
When it comes to mixing different speeds, the only way to really find out is to try it. It depends on brands and speeds. PC133 can be put in with PC100, but it will be downclocked to PC100. Same thing goes for PC2700 down to PC2100. I don't think PC3200 will go down to PC2700 if I recall correctly. But I could be mistaken. I've also seen some different brands not work like others when it comes to downclocking. Give it a shot, but I can't guarantee you won't damage your board. If you get beeps (or one constant one), it ain't working. Give it a shot. That's my two cents. I'm sure Dawei can shed some light on the topic.

DaWei

I have not designed any RAM in years, but essentially, here's how it works: you can mix RAM so long as the slowest is fast enough for the bus speed. You can't mix (generally speaking, or without trouble, or without extra circuitry) technologies or types with different bus pinouts.

Here's the basics of what happens: the processor puts the address on the bus; there's some delay while all the address lines stabilize to the proper state. There's some delay while the memory cells react to those states and place data on the data bus, and delay for all the data lines to react and settle down. You can then strobe in the data (this is a read, obviously). There's some additional delay for the data to stabilize in the processor. At that point you have the data, but the memory needs to hold it there for the delay in removing the strobe. There'll be additional delays before you can read from that section of memory again.

Because of signal degradation due to pushing signals at the speed of light (nearly) down imperfectly terminated traces which are, nowadays, long in terms of their wavelength, accessing off-chip memory cannot be done at anywhere near the clock speed of the processor, itself. That's why onchip cache is used, and why your front-side bus is clocked at a lower frequency. The more cache, the better off you are.

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Wizard1988

Yeah basically if you mix ram of two different speeds most motherboards will make all of your memory run at the slower speed. If I am not mistaken DDR RAM works faster when you are running it in doubles of the same size.

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DaWei

No, your motherboard won't. Your motherboard works at its speed without any ability to evaluate what you hang on it. At the very least you would have to imbue your BIOS with the intelligence to decide this issue. I don't know of a single BIOS that has the ability to do this. Many of them, however, will listen to your advice. If you get it wrong, bye bye Charlie.

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Wizard1988

So i can put in a stick of memory running at 400MHz along with another running at 333MHz and all my RAM can run at 400MHz? How the heck do they make that work?

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DaWei

I think you should read the posts again. Your 400 can run at 333.

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Komodo

I'm thinking about buying this: http://www.tigerdirect.com/applicati...Tab=2&NoMapp=0
Then just throwing more ram in it, and possibly a better CPU eventually, it only comes with 1 GiB of RAM and it's the cheapest Core 2 Duo.
the RAM in that is 533MHz and I'm not sure what the timing was.

Before I go and buy ram to put in it, I wanted to know if I put a stick in there that was 800 MHz, and had 4-4-4-12 timing and say the ram already in it was 5-5-5-18. Would it work? or would it just go at the slower timing? I can't find a straight answer that everyone can agree on...

as for my first problem, I think I'll just buy two 1 gig sticks to add to the 512 sticks...

EDIT: I'm gonna consult google again and see If I have better luck than earlier.

DaWei

You read the posts, too. Your motherboard hasn't the foggiest notion what your RAM is. It doesn't adjust. If you want to adjust it, then overclock it. It won't know the difference, because it won't know that it's running hot or melting down. Your FAN or your CPU might know the difference, if it has a sensor, but that's just an automatic switch. No one blows processing cycles on sensing and adjusting clocks for the motherboard memory in el-cheapo (means 'all') desktop-type systems.

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