I am wanting to put a 512mb pc133 sdram stick in my comp. When i look them up to buy online, they have high density and low density. I need to know which i need, i will give you some specifications of my computer. Its and asus model, series CUW-AM. The chipset is Intel Whitney i810. If you need anymore info tell me ;)

I would be very hesitant to purchase a 512Mb RAM module for that system. The model number you quoted is the motherboard id, by the way, and the motherboard was manufactured for use in some HP and Dell systems, rather than for retail. I can't be sure of the situation for your board, as Asus do not provide support information for it, but quite a few similar boards of that era had limits on the RAM module size they would accept.

I'd not purchase a module larger than 256Mb for it unless the purchase was a 'try before you buy' arrangement.

Alright, would 384mb of ram be enough to run windows XP? 128mb + 256mb.
I know now that 191mb is not enough to run it efficiently.

Yeah 256MB would be minimum to run decently in my opinion but 384 should definitely be good enough (you could run it at 191MB as well but it may be a bit slow).

Ok cool, thanks alot, also one other thing, is there a certain brand of ram stick i should get or a certain one to stay away from? maybe they are all the same, but i just want to know what brand you would recomend if any.

There are plenty of good brands to pick out, really. But, I would just look at price and speed.

If possible, shy away from high density memory, or at least that's been my experience. That tends to be OEM, lower quality stuff, and had limited compatibility with several systems I've run, including Dells and HPs. It's WAY cheap, but you're taking a risk with it not working in your system.

ok cool, thanks alot, I will stay away from the OEM and high density. OEM is a manufacturer that buys a bunch of computers and then customizes them, to there specifications, and then sell them, like HP correct?

Make sure wherever you buy from will let you return the RAM if it doesn't work, several local places near me would not let you return defective or nonworking RAM- so if you get a stick that is defective or not compatable with your pc you would be out of luck. Circuit City has a 14 day return policy on RAM and Newegg.com are nice enough to let you return or get a credit if it doesn't work out so I would go with them if you don't know of a better place (Circuit City can be pricey though).

OEM in this sense basically means unpackaged, unbranded cheap RAM modules. It carries more risk of failure, and more risk that modules from different factories will have conmflict with each other. Hynix, Kingston and Kingmax are manufacturers which still have SD-RAM available for purchase.

I was just wondering if there is a way to limit how many megs of ram your comp uses? say if you 256mb ram can you limit it to use only like 230mb? I am asking because my friends computer says it has 511mb ram, im just wondering how and why they use 511mb instead of 512mb. I have also seen other weird numbers.

Crucial Technology says that your motherboard will support a maximum of 512 MB of unbuffered SDR SDRAM. Here's the spec's they post for that memory. (I checked both the CUW and the CUW-B motherboards. They are the same. Your specific model, because it was manufactured specifically for OEM use (Original Equipment Manufacturer's such as Dell, Compaq, Gateway, etc...) is not listed on this site which only lists retail versions.
Information on the
ASUS CUW

  • 168-pin DIMM Banking: 3 (3 banks of 1)
  • Chipset: Intel 810
  • Error Detection Support: ECC and non-ECC
  • Max Unbuffered SDR SDRAM: 512MB
  • Module Types Supported: Unbuffered only
  • SDR SDRAM Frequencies: PC66 and PC100
  • Supported DRAM Types: SDR SDRAM only
  • USB Support: 1.x Compliant

Pricing is available here too: http://www.crucial.com/store/listparts.asp?Mfr%2BProductline=ASUS%2B+Motherboards&mfr=ASUS&cat=RAM&model=CUW&submit=Go

And finally, a little (perhaps a lot)(got to put on my "engineering" hat) about "density" of RAM.

DEFINITION: RAM Density is the capacity or size of a DIMM module or the capacity or size of each DRAM unit on a DIMM or RIMM. Density is normally referred to in megabits (Mb) when referring to DRAM units and in megabytes (MB) when referring to an entire DIMM module.
DENSITY vs. SPEED: When trying to determine what kind of RAM you need, the density of each DRAM unit on a DIMM is probably more important than the speed of the DIMM. For example, PC133 DIMMs are backward compatible to PC100 and PC66. On the other hand, 256 and 512 megabit technology DIMMs will not work in many motherboards.
[img]http://supcontent.gateway.com/support.gateway.com/images/ub/ub_clear.gif[/img]How To Determine RAM Density: It's hard to figure out the density of a DIMM because there are multiple industry "standards" on how describe a DIMM, many of which are contradictory. Some retailers list the capacity of each DRAM unit in MB and the number of DRAM units on the DIMM. For example, a 256 MB 16X16 PC133 Non-ECC Unbuffered DIMM has 16 DRAM chips, and each chip is 16 MB in size. The density of each DRAM unit is found by multiplying 16 MB by 8 to get the value in bits rather than bytes (one byte is 8 bits). In this case, the density is 128 Mb.
What Your Motherboard Will Take: You may know that the maximum size RAM module your computer will accept is 256 MB and that it needs to meet a specific specification, such as PC133. Assuming the naming scheme of the last step, if you were to purchase a 256 MB 32X8 Non-ECC PC133 Unbuffered DIMM, the density is 256 Mb. This was determined by multiplying the number 32 by 8 bits. But because compatibility is based on the density of EACH DRAM unit on a memory module instead of the capacity of the DIMM as a whole, this DIMM probably won't work in your machine.
Explanation: A motherboard that only accepts 256 MB and smaller sized DIMMS will work only with memory that is based on 128 Mb technology or lower. (This is the case with your motherboard). The DIMM in this example has 8 DRAM units, each with a capacity of 32 MB. If 16 DRAM units were used, the capacity of this DIMM would be 512 MB, and it would only work in motherboards that accept 512 MB DIMMs or higher, even though it is just 256 MB in size. This is due to the density of each DRAM unit on the DIMM.
What Will Happen? Remember that maximum capacity is based on the density of each DRAM unit on the DIMM and assumes the maximum number of DRAM units are on the DIMM. If you try to install a higher density DIMM than your computer can handle, one of two things will happen: 1) Your computer will not boot, and you will receive memory POST beeps, letting you know there is a problem. 2) The motherboard will only recognize half of the memory.

So...my recommendation would be one of two things: Go to one of the memory sites and use their scanner and go with their recommendations, or...since you have three banks with one slot each, I'd use the lower density memory configurations. That is to say, if you want 512 MB of SDRAM, don't buy one DIMM of 512 even though it may be available. Instead use two 256 MB DIMM's, or if you're shooting for 384 MB, use three 128 MB DIMM's or one 128 MB and one 256 MB. And make sure that you do the math - take the first number of --x-- and multiply it by 8 to get the density. You don't want the answer to exceed 128.

Crutial Technology http://www.crucial.com/ has a scanner and so does Kingston at http://www.kingston.com/. Good luck on your upgrade!

commented: HOLY SMOKES! Great explanation! +5

ok here it is im trying to put a 256mb sdram pc133 in my computer, now if you are facing the motherboard i put the 256mb in the left slot, then i put the 128mb in the right slot, I turn on my computer and nothing happens. the "hp invent" logo comes up but nothing else it just stays there. So then i I tried swithing the slots, I put the 256mb in the right slot and the 128mb in the left slot, it goes a little further than the other combination. But at one point it stops and says, "not enough extended memory to run windows" I mena what is going on here? The 128mb runs fine by itself. I dont understand what is going on. BTW im running wiindows ME socket 370 ASUS mobo and an intel 810 chipset i believe. please help!

Went ahead and merged these two threads together. Since you're asking a lot of memory-related questions, please keep them all in one thread.

Thanks!

The 128mb runs fine by itself. I dont understand what is going on.

In which slot?

Try the 256Mb stick by itself in that slot. If the system doesn't recognise it correctly and work OK with just that module installed, then the 256Mb module is incompatible with the motherboard!

So it is in no way that my computer just cant handle that much ram, if so im just going to go with kingston, as you first suggested and return the rosewill chip.

You're making jumps in reasoning there that I'm not saying. Did the 256Mb module work? It may be that your motherboard is requiring double-sided modules for larger sizes perhaps. Some older boards will not recognize RAM modules larger than 128Mb unless they are 'double-sided'.

Note: That does not necessarily mean RAM modules with RAM chips on both sides. It means modules with a particular configuration regarding how the chips are linked to each other. Some 'double-sided' modules may have RAM chips on only one side of the module!

Well yes the 256mb ram module works to a certain extent. almost always when i put it in the left slot it will not work. But when i do put it in the right slot it is hit or miss. Alot of the time i can get up to the desktop, click on something then the computer will restart. At one point i ran the computer in safe mode and it worked and i went to my computer properties and it said that it was there. Now the cases where it actually doesnt restart when get to the desktop it will most likely freeze within 5 minutes. So no it doesnt work properly at all. lol I know i dont explain myself well enough alot of the times and it is frustrating for yall to try and help. But i do appreciate the help you and all the moderators and everyone else offer, its greatly appreciated :)

It was recognised as 256Mb? If so it's simply incompatible with your motherboard. If it was recognized as only 128Mb, then that indicates a need for dual-sided RAM.

awww ok, yes it was recognized. So my best bet would be to go with kingston, although i just want to make sure, I was told to stay away from the kingston(OEM), so would i want to purchase kingston(retail)?

ok ok, im going with kingston but what is OEM in the way of ram? should I purchase OEM or RETAIL? The last purchase i made was Rosewill RETAIL, and turned out incompatible. thanks

I'd steer clear of anything which is labelled OEM. Things are done a little differently in the US than they are here in Australia, where you generally cannot purchase OEM versions of products. those are unpackaged (and often unbranded) versions of retail goods, which are produced and sold for the use of system assemblers. After-sales warranty and support can be a problem, because usually the company manufacturing the product will offload the responsivility for support on to the system assembler, rather than handling it themselves. Buy retail versions of products.

Avoid unbranded RAM like the plague, and try to stick to the reputable manufacturers:

Corsair
Geil
Kingston
Kingmax
OCZ

thank you, hopefully this will put an end to my nightmarish ram problem :)

I sincerely hope so, and you have the honour? of being the last person I assist on TechTalk for 2004!

Truck's packed and I'm off to the bush till sometime in the New Year :D

LOL!

So...my recommendation would be one of two things: Go to one of the memory sites and use their scanner and go with their recommendations, or...since you have three banks with one slot each, I'd use the lower density memory configurations. That is to say, if you want 512 MB of SDRAM, don't buy one DIMM of 512 even though it may be available. Instead use two 256 MB DIMM's, or if you're shooting for 384 MB, use three 128 MB DIMM's or one 128 MB and one 256 MB. And make sure that you do the math - take the first number of --x-- and multiply it by 8 to get the density. You don't want the answer to exceed 128.

Crutial Technology http://www.crucial.com/ has a scanner and so does Kingston at http://www.kingston.com/. Good luck on your upgrade!

The fact that you are having problems with the 256 MB DIMM may be that you haven't done the math I referred to above. Do it by multiplying the first number by 8 and see if it exceeds 128. (Most memory says something like 16 x 8 or 16 x 16, or 32 x 8, etc.) If it does, the density is too HIGH for your motherboard. Your memory DIMM must have the first number no higher than 16 to be compatible with your motherboard. Also, did you ever go to one of the sites I referred to and use their scanner? That too may be the solution to your problem.

And once again a word on "OEM". OEM simply means "Original Equipment Mfr.". Many companies supply versions of their product (Soundblaster audio cards, Western Digital and/or Seagate HDD's, various RAM memory Mfr's, and etc.) directly to a computer company like Dell, Gateway, IBM, etc. and that version is made just for them and referred to as OEM. Microsoft does the same with their O/S - they make OEM versions which the computer companies buy cheaper and preinstall on the PC. The difference between the OEM version and the retail is all about support. If it's an OEM version, you have to turn to the Mfr of the PC for help.

ok, sorry for not reading you post thoroughly rogue, I have gone back and i think i understand now. I need to find a ram module that is 16 x so and so. then I take and that 16*8 and it will work in my comp. But if it is any higher say 32 x so and so. then it wont work because it is over 128 correct? ok i found this right here, it did a scan of my computer and came up with this http://www.4allmemory.com/index.cfm?fuseaction=search.w4s&UniqueId=0067-2511-3608-0173-2480
but im still curious about one thing, why does it say PC100, when i need PC133?

Go back to my very first post on this thread. I said that the specifications I found for your motherboard indicated this. These specifications came from the web site of the Mfr. of your motherboard. Note the highlighted RED entries. This indicates that your motherboard is designed for PC66 and PC100 DIMMs.

    • 168-pin DIMM Banking: 3 (3 banks of 1)
    • Chipset: Intel 810
    • Error Detection Support: ECC and non-ECC
    • Max Unbuffered SDR SDRAM: 512MB
    • Module Types Supported: Unbuffered only
    • SDR SDRAM Frequencies: PC66 and PC100
    • Supported DRAM Types: SDR SDRAM only
    • USB Support: 1.x Compliant

    Pricing is available here too: http://www.crucial.com/store/listpa...l=CUW&submit=Go
    And finally, a little (perhaps a lot)(got to put on my "engineering" hat) about "density" of RAM.

    DEFINITION: RAM Density is the capacity or size of a DIMM module or the capacity or size of each DRAM unit on a DIMM or RIMM. Density is normally referred to in megabits (Mb) when referring to DRAM units and in megabytes (MB) when referring to an entire DIMM module.
    DENSITY vs. SPEED: When trying to determine what kind of RAM you need, the density of each DRAM unit on a DIMM is probably more important than the speed of the DIMM. For example, PC133 DIMMs are backward compatible to PC100 and PC66. On the other hand, 256 and 512 megabit technology DIMMs will not work in many motherboards.

I looked at the site you gave and they also recommend PC100 DIMMs. They also guarantee that these will work or your money back. I'd buy two of the 256 MB sticks and upgrade my RAM to 512 MB which is the max your MB will support. I don't know where you came up with the PC133 specification??? You could put them in, but you'd be wasting money because your MB will limit the speed.

heh, im not sure where i got either, well thank you for your assistance :D

im sorry for bringing up a very old thread, but i just need to know something. I just looked at the specs of my computer, and it says I can run 66mhz or 100mhz SDRAM, now a long time ago I put a stick of pc133 128mb sdram in, and it is in there this very moment and is working like a champ....how am I able to be using this speed of 133mhz ram?

Hi, I'm new - just a question relating to this topic -

I have a 128mb stick and i'm inserting a 256mb stick -

Do I have to have them inserted in a certain order - e.g. 256mb first and then the 128mb or vice versa?

thanks for any help - sorry to interrupt the thread

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