At the risk of derailing the topic I'll go in depth into my tale of woe regarding the RAM.
Basically, I started getting errors. One of the less drastic signs is that Firefox will suddenly shut down on me. Once that happens, if I don't reboot then after a while longer I'll generally get a BSOD (blue screen of death) error. The blue screen errors vary widely, it seems that the errors don't always mean anything. I've gotten errors in USB drivers, in the NTFS system, all over. It appears that when the RAM causes problems they're not consistent, although there are a few blue screen errors that are apparently most likely caused by bad RAM.
I verified that it was due to the RAM because I tried using my two sticks one at a time until I found the one that worked reliably. But then eventually the good one died as well and I had to replace the set. This happened twice now. If my system is running true to history then in another week or two this remaining good stick will start giving me errors too. The thing that has me burned up is that I've now seen reports of other people having the same problems, it appears that Crucial changed the type of RAM used in these sticks and the replacement model isn't near as good or reliable as the original even though it's being sold under the same name with no indication of the hardware change.
If the nature of the reduced speeds that you're seeing is of having to wait for hard drive crunching when you're trying to load up a new program or switching between them, then that could indicate that your system is having to page data to the page file more frequently, and that could be because you have less RAM. Have you checked to see that your system is still seeing all three gigabytes? If you're using windows you can find out by going into the control panel and then selecting system, the first screen (the general tab) should tell you how much memory your system is seeing.
I wouldn't expect slowness but no errors to be symptomatic of RAM problems. I mean maybe it could indicate that your RAM is running too slowly, but you'd have had to make that change yourself in the system's BIOS. It shouldn't just spontaneously slow down on its own, even if it's degrading the system shouldn't automatically slow it down in reaction, it should keep running it at the normal speed and you should be seeing errors. On the other hand, during my troubleshooting of the first set of RAM I did have a day where my system just didn't see one of the two sticks. Ironically that may have made it run more reliably, because the missing stick might have been the unreliable one.
As to taking out one stick at a time and testing the remaining ones... that may not help you. Cutting back on the amount of RAM in a system will tend to make it run slower anyway. I mean if you pull a stick and then find that the system is running faster that may be a good hint that you've found the problem, but it's not what I would expect to happen even if you did pull a bad one.
You can check this out:
http://www.memtest.org/
It's a memory tester that you can get in many formats, from a floppy disk image to a CD image to a version meant to be used on flash drives. You HAVE to boot to the medium you install it to, it can't be run from within windows. In my case it doesn't always show errors, it seems that I have to stress my memory out first and then it shows errors. I don't really know what this means. But it's free, you have nothing to lose by trying it other than the time it takes to run. It will keep running continuously if you let it, it doesn't stop at the end of the cycle, but it'll give you a message when it's completed a full cycle.
