Why exactly don't two RAM kits work together?

Karlovsky120

Reputable
Jan 9, 2015
4
0
4,510
I have a situation like this.

I'm trying to revive a rather old computer (MOBO with 478 socket and Pentium 4 sticket onto it) which uses old DDR400 RAM type.

It originally had 2x256MB which I want to replace with 4x1GB (the MOBO supports it).

Buying new ones is not an options since, at cheapest, it would cost me over $120 which is far more than I want to give for such an outdated technology.

Getting used ones is also a bit of a hassle since it's hard to come by people who are selling 1GB sticks, let alone 4x1GB sets.

I have bought 2x1GB set and plugged it in free slots of the MOBO, so I had 2x1GB and 2x256MB for a total of 2.5GB.

However, the computer would just randomly froze after about 10min of use, a problem which was solved by removing the two smaller kits. The comupter now works in dual channel mode.

Now I'm trying to get another 1x2GB kit to put it in, but I'm afraid it won't work. I also know that it might.

This is the mobo in question, with a BIOS that has never been flashed, so I don't know what my options are regarding to changing the timming and/or voltage:

http://www.gigabyte.com.hr/products/product-page.aspx?pid=1863#sp

I'm unsure of the exact RAM installed (the 2x1GB kit) and I can't get to it right now, but I'm guessing it's only important relative to the other potential kit.

What are the requirements for the RAMs to work together, it doesn't seem to be explained anywere I looked so far.

The bottom line is, I'd like to get the computer to 4GB of RAM and, if possible, to make it work in dual channel. What do I need to look for when buying another 2x1GB kit?
 
Solution
With older rigs and DRAM chances are fairly good if they use same speed, timings and voltage as most all pretty much kept to JEDEC DRAM standards (newer DDR3 and DDR4 is very different as JEDEC 'standards' are so out of date ;) Also things that can play in are the chips config i.e. size and number of chips used, but even the PCB and down to the solder used can affect sticks of DRAM

Tradesman1

Legenda in Aeternum
With older rigs and DRAM chances are fairly good if they use same speed, timings and voltage as most all pretty much kept to JEDEC DRAM standards (newer DDR3 and DDR4 is very different as JEDEC 'standards' are so out of date ;) Also things that can play in are the chips config i.e. size and number of chips used, but even the PCB and down to the solder used can affect sticks of DRAM
 
Solution