quick ram question

  Looking at buying a used older stick of ram to get some more use out of this computer. I have 256mb of ram, pc2100 ddr 266 made under the name NANYA, i believe.
  Ive been looking around on ebay and the prices are good but is it okay to mix sizes and brand names at all?

  I have a link below but i cannot tell what size it is so anyone want to identify it for me?

http://cgi.ebay.com/1024-Mb-184-PIN-DDR-DIMM-PC-2100-266Mhz-PC2100-1GB-REG_W0QQitemZ170049578193QQihZ007QQcategoryZ74942QQssPageNameZWDVWQQrdZ1QQcmdZViewItem?hash=item170049578193

>>4
To clear some things up that aren't so clear, now that I actually look at what I posted:

- You CAN use different brands.  No problem at all.
- In almost all cases, you CAN use different sizes.  If the RAM slot/mobo itself doesn't support that size, it may only use the amount it knows how to address, or it may not work at all.
- For DDR SDRAM, you can mix and match speeds at will.  However, if you have different speeds, the lowest speed will be used for all, and if your mobo doesn't support a speed, it will be downclocked until it's compatible (going to the highest the mobo supports or, if there are other sticks present, the lowest speed present).  The tech market is kinda funny, where older tech doesn't necessarily get cheaper and may in fact get more expensive as it becomes rarer.  This means that newer, backwards compatible solutions are sometimes cheaper and provide future proofing.


Now, I noticed when I looked at the link again that this particular RAM is both Registered and uses ECC.

http://en.wikipedia.org/wiki/Registered_memory
http://en.wikipedia.org/wiki/Error_detection_and_correction#Error-correcting_code

tl;dr:  These options are generally for servers where high performance and reliability are more important than cost and speed.  You should see if your mobo supports these, or there could be problems.  Personally, I'd say (now that I noticed this) that you should skip this auction.