Added some RAM, and now issues

Wow... it is cheaper (which is my #1 factor in picking parts.... easy to see why I got in this mess)

What can I do to find out if it's compatible with my old RAM (presumably handpicked to match my motherboard by the more informed me of the past)

My old ram has a brandnamelooking symbol that's an 'S' in a diamond, not completely unlike the Superman symbol, and text on the eight rectangular ram black things that says "46V16M8"

*laugh*

Just remember to always look at the tech docs for the parts you want to buy first. Make sure that all of your parts are as compatible as they can possibly be. And it's worth reading reviews on different parts and manufacturers, if you aren't familiar with the field yet. Spending an extra few bucks for a part the actually works is usually worth it.

Fifteen minutes of research can save you incredible amounts of time later on!

I haven't a damn clue who the logo belongs to. It could belong to anyone of numerous companies, anyone of which could be sold under other monikers. Hopefully that won't matter.

I know that the 46V16M8 chips are only found in DDR266 RAM. So, at the very least, you've got the correct RAM for the motherboard.

I say get the Kingston and try it alongside that stick you've already got. I'd place an even bet that'll it's work fine.

That's what I'm likely to do.

Went though my drawer of paperwork today- looks like all the documentation for my computer parts is elsewhere (probably boxed up in my parents garage).

Meh, you can get all the docs you need online anyway.

Let me know how it turns out.

Some ram, but not all ram are designed to be backwards compatible and will speed step to the the speed that the fsb is set to. If the chip is not capable of this it will not speed step and will likely cuase errors if not work at all.

You should always ensure that you are using ram that either is backwards compatiable or meets and not exceeds the specs of your board. As has been mentioned here not all chips are of the same quality, density, or response time. Some motherboards require specific densities and response times, more and more OEM vendors like Dell require specific grades of ram if you are upgrading a prefab system.

Updated my RAM today... running on 512, with the new ram suggested by Monarch and my computer's original 'mystery RAM.' The incompatible stuff is gone. So far, so good.

A "Rule of Thumb" when I upgrade ram. I always buy new sticks that match. If I had a 256MB stick and I wanted to upgrade to 512MB then I would buy 2 256MB sticks that match. Yes I know it seems wasteful however it cures allot of problems. I never mix ram anymore. It is too painful. For example I own a Dell and they are FUSSY about ram. Personally if you were me I would buy two matching sticks of 512MB ram and have a blast with a full GB. 512MB will just barely get by. You figure XP is taking up 256MB of your ram just to run your computer.

I think it is just a mismatch, u don't need driver to install a ram, to minimize problems, make sure u know what speed, ur ram is, and what timing it got and match both pair.
also make sure what your motherboard support, such as high dent., low dent., ECC, and all that stuff....

Run CPU-Z from http://www.cpuid.org/cpuz.php . Once you've loaded it up go to the SPD tab and it should list the type of RAM in there.

By the looks of the description of the motherboard (Abig KG7), your board supports our 184-pin DIMM sockets support up to 4 GB PC1600/PC2100 DDR SDRAM module, so I'm assuming that PC3200 should work aswell. Try swapping the sticks around and maybe that could solve the problem. If not, then try exchanging the stick that you just bought.