[Ace]

I got a PC-100 motherboard and I want to buy more RAM for it. Now I went to London Drugs and they said that PC-133 RAM will work on my motherboard because somehow the RAM will lower its speed to 100Mhz instead of 133Mhz. Does this actually work?

[duhmez]

yes it will work fine. PC 133 is rated to run at 66,100, and 133 .

[jimf43]

pc133 is usualy concidered backward compatable with pc100. I'd be much more concerned about mixing the two. You're much better off using matching sticks, and personally, I'd want it supplyed by a more computer knowledgeable outfit than 'London Drugs' ;-). Most of the outfits that I've delt with here in the states will work with you to insure a sucessfull upgrade.

[mezron]

Quote:

yes it will work fine. PC 133 is rated to run at 66,100, and 133 .

That used to be the case. Some of the newer stuf is 133 only, 100 only, etc. You can't really assume that 133 is backwards compatible anymore. I just found this out the hard way a couple months ago.

Jim

[sapiens74]

If can find a cheap 512mb stick go with whatever you can get


I wouldn't invest a lot in that memory

[Champion_R]

Make sure 512MB sticks are supported if you are going down that road. Also when buying the memory MAKE SURE you ask them if it'll work at PC-100. If they say it does and it doesn't you are covered :P

PC-133 memory should be backwards compatible. I run PC-133 at PC-100 in one of my PCs

[jmmijo]

Here's the biggest thing to watch out for, if you install a new stick of memory into the machine and it only shows half the memory of that stick, then your motherboard may not properly support high-density ram modules. Check the motherboard manufacturer for a BIOS update to see if this resolves the problem. Do this only after testing the new stick of ram out. Also the tips about using a single 512MB module and about mixing different speed modules in the same machine are good but again you have to do some testing to see if this is the case with your particular setup.

Also, you didn't mention the OS you're using, this will help determine the optimal amount of ram to use.

For Win 9x up to 512MB without the vcache patch.

For Win NT/2K/XP any amount you want, up to the maximum that the motherboard can address. With yours it could be listed as a maximum of 768MB in which case you can most likely only use 256MB memory modules. Check the user manual or the manufacturers website for more info on this.

[adamvjackson]

Quote:

Here's the biggest thing to watch out for, if you install a new stick of memory into the machine and it only shows half the memory of that stick, then your motherboard may not properly support high-density ram modules.

Sorry to nitpick, but that's not necessarily correct. If adding a new stick only half is addressed, there's a good chance that the motherboard cannot support double-sided memory modules.

As an example, my current workstation motherboard, an Asus P4B533-E with the Intel 845-E chipset, supports the following memory configurations:

Slot 1: Any single or double-sided module, up to 1GB.
Slot 2: Any single or double-sided module, up to 1GB.
Slot 3: If slot 2 has a double sided module, then slot 3 must be vacant. If slot 2 has a single-sided module, then only a single-sided module may be placed in slot 3.

Note that if single-sided modules are used in both slots 2 and 3, they may each be 1GB sticks, for a system (chipset) total limitation of 3GB.

Hope that clears things up a bit, and jmmijo was correct about Windows 9x and the vcache patch.

[jmmijo]

Perhaps so, I've come across quite a few 256MB modules that for whatever reason wouldn't work in older P2/P3 motherboards, however replacing them with double-sided PC66/PC100 memory modules worked fine. So I hate to nit-pick as well

Saying it doesn't support double-sided is not a good description as many older SDRAM modules can be either single or double sided including newer 256MB memory modules, but these are usually DDR instead of SDR memory

Now if you description of double-sided is different then what I interpret it as then that is where the mis-communication comes from...

[Ali]

Quote:

Quote:

Here's the biggest thing to watch out for, if you install a new stick of memory into the machine and it only shows half the memory of that stick, then your motherboard may not properly support high-density ram modules.

Sorry to nitpick, but that's not necessarily correct. If adding a new stick only half is addressed, there's a good chance that the motherboard cannot support double-sided memory modules.

As an example, my current workstation motherboard, an Asus P4B533-E with the Intel 845-E chipset, supports the following memory configurations:

Slot 1: Any single or double-sided module, up to 1GB.
Slot 2: Any single or double-sided module, up to 1GB.
Slot 3: If slot 2 has a double sided module, then slot 3 must be vacant. If slot 2 has a single-sided module, then only a single-sided module may be placed in slot 3.

Note that if single-sided modules are used in both slots 2 and 3, they may each be 1GB sticks, for a system (chipset) total limitation of 3GB.

Hope that clears things up a bit, and jmmijo was correct about Windows 9x and the vcache patch.

If it is any of the i845 chipsets from intel, then it's 2Gigs of ram. sorry, ASUS website is just too slow for me to chech the mobo. (why their site sucks so badly, i can never find anything there, i hate their website ;( )
My Gigabyte Mobo is like that. it has a i845PE chipset, BUT it has 3 DDR memory sluts! it's just that the 2nd and the 3rd one is shared. (that's only for DDR SDRAM and i have never seen it for SDRAM)

Come on, don't make it complex. just get a stick of ram and stick it in and see if it wors. how bad could it be? worse case senario is that your mobo may not support 1 stick of 512MB on each memory bank, or you can't mix it with the old one.

[Ali]

Another suggestion: go to crucial website, find your mobo model number or name and check their listings for their compatible memory sticks! you can always close the browser and not to buy it from them!