DDR2 backwards compatibility

Omnutia

I just need to double check something.
A while ago, Churba suggested that I keep a stock of RAM sticks around so that when I'm fixing people's computers, I can just throw and extra gigabyte or two in.
Does anyone know of any problems that might arise from putting faster ram in a slower computer? e.g. PC2-6400 in a PC2-5300 system.

It may seem like a simple question but I want to be absolutely sure before buying a bunch of RAM sticks.

Apreche

It depends on the specific motherboard and specific RAM stick. Check the motherboard manual, and it should say what RAM sticks it supports. Keep in mind that you will have to lower the RAM speed if the sticks are way low, and that might significantly decrease performance. RAM is so cheap, I would suggest just buying the most optimal ram for the given board.

Omnutia

Just to clarify: The reason I wanted to put faster ram in older computers is that older (and thus, rarer) ram is more expensive and it also saves me having to order each time as I can keep three sticks of the latest RAM in stock instead of having to order individual sticks each time, which takes longer.

If I have to order a separate stick each time, I suppose that's just what I'll have to do.

George Patches

I advise against this highly. It has been my experience that as RAM has gotten faster (SDR => DDR => DDR2 => DDR3) that it has gotten considerably more fickle. Back in the day, you had SD ram and if you put a stick of that in, odds are it would work. That is simply not the case today. My brother had a set of DDR2 800, worked great in my computer so I decided to buy some for myself. I bought the exact same set and it wasn't compatible with my computer no matter how I configured it. That same set worked fine in my brother's computer, and my brother's set worked fine in mine. My brother upgraded to 1066 ram, but he can't get it to run at its full speed, it fails after 900 MHz.

Seriously, swapping ram these days is just opening yourself to a world of hurt you don't want to get involved in.

Omnutia

Well, looks like I dodged that bullet.

Apreche

I advise against this highly. It has been my experience that as RAM has gotten faster (SDR => DDR => DDR2 => DDR3) that it has gotten considerably more fickle. Back in the day, you had SD ram and if you put a stick of that in, odds are it would work. That is simply not the case today. My brother had a set of DDR2 800, worked great in my computer so I decided to buy some for myself. I bought the exact same set and it wasn't compatible with my computer no matter how I configured it. That same set worked fine in my brother's computer, and my brother's set worked fine in mine. My brother upgraded to 1066 ram, but he can't get it to run at its full speed, it fails after 900 MHz.

Seriously, swapping ram these days is just opening yourself to a world of hurt you don't want to get involved in.

Uh, this has nothing to do with the RAM, and everything to do with your motherboard. Each motherboard takes different RAM at different speeds. It is pretty clear that you and your brother simply had different motherboards with different memory requirements and configurations.

It's really simple guys.

1) see what motherboard you have.
2) research the optimal RAM for that motherboard.
3) RAM is so cheap, you might as well max out the motherboard with the optimal RAM.
4) You'll never need to upgrade RAM unless you replace the mobo, in which case go back to step 1.
5) If RAM breaks, replace with the exact same type of RAM.

George Patches

Uh, this has nothing to do with the RAM, and everything to do with your motherboard. Each motherboard takes different RAM at different speeds. It is pretty clear that you and your brother simply had different motherboards with different memory requirements and configurations.

This was the exact same set of ram, same Newegg item number. One set worked in my computer, one set didn't. Whether this is a mother board or ram issue I really don't care. My point is stocking ram to throw in someone's computer at a moment's notice is just not going to work. Not since the days of SD ram have I had good luck with throwing random sticks of ram that were laying around in a computer and had them work.

Apreche

This was the exact same set of ram, same Newegg item number. One set worked in my computer, one set didn't. Whether this is a mother board or ram issue I really don't care. My point is stocking ram to throw in someone's computer at a moment's notice is just not going to work. Not since the days of SD ram have I had good luck with throwing random sticks of ram that were laying around in a computer and had them work.

You said.

It has been my experience that as RAM has gotten faster (SDR => DDR => DDR2 => DDR3) that it has gotten considerably more fickle.

This is patently un-true. If anything, RAM is better now than it ever was before. Even no-name brand sticks are perfectly stable. The only thing is that back in the SD days, there was a short period of time when most home computers were using the same kind of RAM. RAM development slowed down, and did not improve considerably. Thus, most motherboards all supported the same thing.

In the days prior to that, and also at the present time, there is a wide variety of RAM out there. And every motherboard is different. The RAM isn't more fickle. The only thing wrong in your situation was your failure to do your research.

George Patches

The only thing wrong in your situation was your failure to do your research.

How is trying a set of ram, seeing it work, buying the same set and having it be incompatible a failure to do my research?

Apreche

How is trying a set of ram, seeing it work, buying the same set and having it be incompatible a failure to do my research?

If the motherboards were not exactly the same model in both computers, then you should know that different motherboards need different types of RAM. Just because it fits in the slot does not mean it will work.

George Patches

If the motherboards were not exactly the same model in both computers, then you should know that different motherboards need different types of RAM. Just because it fits in the slot does not mean it will work.

I think we have a miscommunication. I took the ram out of my brother's computer, put it in mine and it worked fine. The set I ordered from newegg that was the same model wouldn't work.

And with a aftermarket motherboard (like ASUS or Gigabyte) how are you supposed to know what will work with it?

Apreche

I think we have a miscommunication. I took the ram out of my brother's computer, put it in mine and it worked fine. The set I ordered from newegg that was the same model wouldn't work.

That's a perfectly possible situation. There are many factors that could have contributed to this situation. What is the EXACT same RAM? Was it a different number of sticks? Were they different sized sticks? Did they have a slightly different speed or CAS latency? Did you put them in the right slots? There's a lot of differences between RAM you may not realize.

And with a aftermarket motherboard (like ASUS or Gigabyte) how are you supposed to know what will work with it?

You go to the ASUS or Gigabyte website and look it up.

sK0pe

And with a aftermarket motherboard (like ASUS or Gigabyte) how are you supposed to know what will work with it?

It is usually always listed in Asus motherboard manuals and all you have to do is peak at an overclocking forum, look up your exact motherboard and there will be the most overclockable RAM which is also the most stable.

If you tried your brother's RAM to see if it worked in your computer then bought the exact same RAM for your motherboard, then just return the RAM for a replacement or check if there are some inconsistencies with the RAM chosen.

I had to return my first 2 sticks of OCZ RAM because they were unstable when overclocked so OCZ sent me a fresh pair which work fine at an even lower voltage.

George Patches

That's a perfectly possible situation. There are many factors that could have contributed to this situation. What is the EXACT same RAM? Was it a different number of sticks? Were they different sized sticks? Did they have a slightly different speed or CAS latency? Did you put them in the right slots? There's a lot of differences between RAM you may not realize.

Same part number ram. Same number of sticks. Same size sticks. Same timings and CAS latency. Same slots (though I tried all of them). Seriously, I've been building computers for close to a decade I know the drill. These sticks were as near as I could tell exactly the same. One set worked in my computer, the other didn't for no discernible reason. Both sets worked in my brother's computer without issue.

Apreche

Same part number ram. Same number of sticks. Same size sticks. Same timings and CAS latency. Same slots (though I tried all of them). Seriously, I've been building computers for close to a decade I know the drill. These sticks were as near as I could tell exactly the same. One set worked in my computer, the other didn't for no discernible reason. Both sets worked in my brother's computer without issue.

It happens. Your one anecdotal experience is not representative of a greater trend of newer RAM to be less good.

George Patches

It happens. Your one anecdotal experience is not representative of a greater trend of newer RAM to be less good.

So, you spent 4 posts trying to say, "you're stupid and don't know what you're doing" and now you say, "your sample size of 1 is not enough to prove anything."

Whatever.

Σπεκωσποκ

At the beginning, this seemed to be true:

"you're stupid and don't know what you're doing"

When you clarified, this became true:

"your sample size of 1 is not enough to prove anything."

Nothing to get your panties in a bunch over.

...

At the beginning, this seemed to be true:

Wrong, at the beginning it was

My brother had a set of DDR2 800, worked great in my computer so I decided to buy some for myself. I bought the exact same set and it wasn't compatible with my computer no matter how I configured it.

Unless of course you meant that it is Scott who is the stupid one and doesn't know how to read. Admit it, Scott fucked up and now just hid behind the general, basically always true, statement of "small sample size means dick".

Σπεκωσποκ

Unless of course you meant that it is Scott who is the stupid one and doesn't know how to read. Admit it, Scott fucked up and now just hid behind the general, basically always true, statement of "small sample size means dick".

Wrong, I meant

At the beginning, this seemed to be true:

Unless of course you meant that it was you who missed the key word "seemed", thus misinterpreting my statement, like Scott and I missing the key word "my", thus misinterpreting gedavids' statement, proving we can read just as well as you. Admit it, you're hiding behind the shoddy defense of "it's a true but general statement therefore it's lazy".

This is far and away the most stupid, pedantic argument to get into, though, so that is that. No more.

...

Wrong, I meant

At the beginning, this seemed to be true:

I was talking about your quotation of gedavids, i.e.

Posted By: gedavids"you're stupid and don't know what you're doing"

Saying that maybe you meant to mean 'stupid' as in Scott being stupid for rolling around his huge ego basically shouting he's the elite, that he knows all, while looking down on gedavids who has to repeat himself multiple times before Scott stops saying "Stupid!" and instead just turns around, says a true statement and disappears.

Your humping of Scott's leg doesn't do much though, he'll just think you're an inconvenience.