Why is ram in pairs

View More Photo Galleries. Unread PMs. Forum Themes Mobile Progressive. Essentials Only Full Version. The info I had when I bought it was that it had just one. My model number has a few configurations, and I kept seeing that models had a max of 16GB with 2 x8.

HP engineer had it apart the other day, and when I asked hi to check, he whipped out the single 8GB and confirmed it has 2 slots and a maximum of 16GB I've noticed slot info is also shown in task Manager now not sure if it used to. I was taught not to just handle RAM unless you are earthed. They way the HP Engineer handled it, was no surprise. Even when you buy ram here, someone just after you pay will whip it out the packaging and stick a sticker direct onto a chip, with no concern over static.

So I'm thinking, maybe I should get a matched pair, from overseas to avoid shop staff handling , then move this current 8 to my work laptop, Is there a benefit to both RAM chips being the same type?

Do I need to think about matched pair. I can't earth myself anyway, they don't seem to have anything connected to earth. With only one memory module its not running "dual channel" which is needed for best performance two 4GB RAM modules is better than one 8GB. Before you just randomly order memory, you must get compatible memory that includes the type and speed. The higher priced Kingston is OK.

You can check what is needed on the Crucial Memory site what we always advised on the Dell forum for non-Dell as it was guaranteed to work in a Dell, and probably the same applies to a HP. My specific model doesn't seem listed on Crucial, but it was their ram I was thinking of. Just ran their system scanner. I found an 8 GB memory module, that is the same as the part number listed in the HP manual for your model. That would be cheaper than buying new memory.

Thanks for doing that. I'm just looking to see if that's available in the UK. Max Output Level: The max manufacturer supported memory would involve two things: 1. Number of physical RAM slots.

You found two Probably, but to be sure check with HP support, or post on their forum. I agree with Firebird's advice on the RAM matching. I have also found that if you mix two different speeds of RAM, the whole memory bus will run at the slowest latency and frequency of the module with lowest common spec.

Yeah I think buying a pair, and moving the existing 8 to my single slotted work laptop which supports up to 8, but has 2 will be the best option. Seems less messy with getting the pairing right.

Wow, I cannot see the actual specifications for this machine. Set on a loop of inputing the product number G0T59AV, Selecting how to see how much ram I can add, which says deduct what's installed from the specified max, which I find by entering my product number and starting the loop again. While the chipset on the laptop may support 32GB, the chipset is likely used in many different laptops from many different manufacturers; some manufacturers will equip their laptops with 4 slots, and some with 2 slots.

With 2 slots you're essentially limited to 16GB, regardless of the fact the chipset can cope with 32GB. I think several things are pointing towards it being 2x8gb maximum. In some ways it is and in some ways it isn't.

PSUs are the same way. Many view them as commodities and don't understand why they should pay more for the same wattage. There is a good reason, they just don't know it. Yes, RAM internals are a lot the same regardless of maker, but different chips do have different properties. The chips made in Japan are pretty widely known to be better quality and higher price than the ones made in China are. That is just something people have come to accept as a fact of life for the most part.

Therefore the RAM cards that use chips from Japan will cost more and potentially be higher quality than those which use chips from China. This matters because it applies most to the lowest common denominator, the chips from China.

The people who are using unmatched RAM are maximally likely to be in the ultra low budget range. If they were in a higher budget range, they could just buy 4 x 4 GBs of some kind and just throw away the 2x 4GBs of a different kind they already have and they wouldn't care about it. The ultra low budget people I am one of those , however, tend to be the most incentivized to get maximal usage out of what they already have and maximally minimize the cost of new expenditures in order to achieve a given set of goals.

This often means they want to buy cheap RAM that doesn't match what they already have because what they already have is more expensive than something else that is available. So you are really talking about a low quality chip from China being stuck in with another low quality chip from China made by some other company. You get all the drawbacks and none of the advantages.

It just takes one tiny defect on one RAM stick to prevent a system from booting completely. From the point of view of the manufacturer of a motherboard, though, they don't want to service calls like this if they can possibly avoid it. All the motherboard maker can really tell you is to send it back to them, they will test it at their own expense, and they will ship it back to you at their own expense.

It is in their interest to limit this to the greatest extent possible. Quite often, if not most of the time, they just test things, figure out that there is nothing wrong with it, and they send it back with a note saying that. A lot of people just RMA things that aren't broken because they don't know what is broken and what is. Your motherboard maker could probably think that your bad ram is the cause of the problem, but they don't really have any desire to try and test your bad ram.

They would rather just tell you to buy something else if at all possible so they don't have to test it. Especially since bad RAM has a habit of working when you don't want it to and only not working when you do want it to work. They could test the sticks for 8 hours, find no errors, and send it back with a note that it is good when it isn't. Really, having a QVL is the most pragmatic way that motherboard manufacturers can limit the amount of money that people on ultra low budgets can damage their bottom line, that is about all there is to it.

Oct 9, 48, 2, , 9, Ram is sold in kits for a reason. Ram from the same vendor and part number can be made up of differing manufacturing components over time. Some motherboards can be very sensitive to this. Although, I think the problem has lessened with the newer Intel chipsets.

Still, it is safer to get what you need in one kit. Raiddinn: For PSUs there are various protections, higher continuous power at "elevated temperatures" and higher overall power output which raises cost and is differentiator. Likewise for every single component in a PC. Hard disks do not come in matched pairs to be used as RAID 0, it will suffice if they are same model, and i haven't tried but maybe even different models.

Even crossfiring is possible with slightly different GPUs. This issue is with running dual or triple channel memory, and not only about generic ram makers, every reputed makers market twin ram modules. Why this is need? Each and every ram tested to work properly in single channel should work with same type in dual channel or should not be allowed to sell. However the question still remains, Chinese make poor quality rams; what exactly is "poor" about them. So what makes their use in dual channel a matter of luck, but not only for generic rams, even branded ones have uncertainty, to a lower extent of course, if not "matched".

What exactly differs in ram modules if they have identical tech specs? What is in "quality" that is not is tech specs, and what could go wrong that makes manufactures to ship matched pairs. I know this happens, I just dont know why? There are not very many companies that make RAM from start to finish. Micron is one of the companies that does. If you go to Crucial's website www. What happens is the Micron company makes say like 1 million of those little black chips on the RAM sticks.

So Micron makes these things and Micron is one of the companies that tests every single part they make in QC. They figure the cost of replacing the sticks is less than the cost of trying to manufacture RAM chips that are Every part that isn't within specs gets tossed into the "fail" bin.

The ones that pass get sent to the next stage in the manufacturing process. Also, I want to point out here that the number and quality of tests performed does matter. Some manufacturers like Micron run a dozen tests on each chip. Other manufacturers may only run 2 or 3 tests on each chip. Also, if given specifications say anything below 10 and above 20 is a fail in some metric, a maker can opt to fail anything below 12 or above The reading of 10 could have been a 9.

If the maker puts the minimum at 12 they can be pretty confident that it would average above 10 if the chip were tested for 10 times as long or times as long.

So what happens to all the chips that are in the "bad" bin? Micron sells them to somebody else that wants them. The buyer doesn't have the capability to manufacture these black chips, but they do have the capability to put them on a board and use them for something if they work. It is easier to put them on a board than it is to make them. Going back to the prior example, if Micron sets the cutoff at 12 but anything above 10 is OK, then there are chips in the fail bin that are rated at both 10 and 11 which are acceptable for use, even though they are below Micron's tolerance level.

The buyer may buy a million of these fails for pennies on the dollar. To get a million fails would require many different production runs because a lot of what Micron makes isn't a fail. The buyer gets these little black chips at pennies on the dollar because a lot of them are actually bad just completely worthless, they have to buy those too just like they are buying the ones that got 11 good but not within tolerance.

The buyer has to try to test each of these parts to determine if they are a "good bad" one or a "bad bad" one. They throw the "bad bad" ones in a fail bin and sell those again to someone else if they can and they keep the 10s and 11s.

With those 10s and 11s, they put them on a board and sell them under their own RAM brand name. Those chips will cause the RAM to fail, but not as often as if the RAM would have been constructed with "bad bad" chips. The distributors who these companies sell to know that they didn't make the RAM chips themselves and they know that all the RAM chips this company uses were failed by Micron, so they won't pay the rates for the RAM from brand x that they would have paid for RAM from the Crucial brand.

They know the quality is worse and they pay less for it in order to subsidize the losses they are going to take on replacements. The distributor then sells the RAM chips it has, some from Crucial and some from other companies using "good bad" RAM at a markup and the retail stores that get it sell it at a further markup.

Micron charged a premium and so did everyone else in the chain all the way up to and including the retail store. At the same time, the rates were cut along the way for the "good bad" RAM because it was known all along that these were made completely with reject chips and the likelihood of the end product needing to be replaced is much higher.

If Micron's QC sets the bar high for its chips 12 - 18 instead of 10 - 20 then maybe That means the end result product is Do you think it is possible that a 3rd company might have tried to do tests on it and see if it could find any 9. If they were getting "bad bad" ram at pennies on the dollar compared to what Micron sold the rail ram to the second company for, do you think there is a potential to try and salvage some of those chips and sell them even knowing the failure rates would be astronomical in practice?

I hope now that you are starting to understand the differences in RAM after this explanation. Thanks Raiddinn for the detailed post. What i got from above was: 1. There is higher probability of a generic RAM failing. Those RAMs are not guaranteed to run a million cycles say and may fail earlier. They may or may not work at elevated temperatures. But : 1. As long as they are OK, they will fulfill their specs. So, If 2 bad ram will not work even in single channel if 2 sticks found goodwill in single channel.

If they are OK in single channel, why not in "dual channel"? Does dual channel have more stringent requirement. If that is the case, I dont know of any. Two rams are tested to be OK in single channel, why matched pair ought to have higher probability of working together.

Or is it like, reputed makers have higher quality chips so they marked RAMs as "matched" and are willing to replace both sticks if only one is faulty so that one has not to hunt for which stick is bad. Due to higher overall QC they will still get less returns. They can sell it for slightly higher cost and for end users the advantage is less troubleshooting hours. If that is the case then there is no technical issues, but i am inclined to believe otherwise.

Why work in single channel with no problem and not work in dual channel? There is no guarantee that dual channel WONT work with mismatched sticks. Said another way Mismatched sticks might or might not work in dual channel mode.

In your case, I suspect that you have installed a combination that the motherboard doesn't support. Check the specs for your computer re. You can also look up your machine at crucial. How satisfied are you with this reply? Thanks for your feedback, it helps us improve the site. Thanks I will check it out. A subscription to make the most of your time.

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