Thinking of adding more memory to your laptop? Buying more memory can often one of the best ways to increase the speed of your laptop. When a computer runs out of memory, the operating system will start using your hard drive store memory temporarily. Unfortunately hard disk is MUCH slower than memory resulting in even the fastest computers slowing down to a crawl.

The good news is that, instead of buying memory from the manufacturer, you can often save some money if you have the right part number for your memory which you should be able to find out by asking questions where you initially purchased your computer or using Google to search for your make, model number and the words memory upgrade.

Always make sure that it is even possible to upgrade the memory. If you are lucky, you may even have an empty memory slot. Other times, you will have to replace existing memory. For example, if you have 2 sticks of 2 GB of memory in your computer and want to add 4 more GB, you may have to remove one of the 2 GB sticks of memory and replace it with the new 4 GB. If you don't know about this ahead of time, you may end up surprised when your computer starts up only claiming to have 6 GB of memory. And what do you do with the stick you removed? Sell it on eBay to recover some of your investment or just keep it as a spare part in a save place -- like the packaging that the new 4 GB of memory came in.

Most laptops and notebooks use a format of memory called SODIMM which is different from regular SDRAM type desktop memory even if the rest of the specs seem to match. It's a physical difference. Also, DDR2, DDR3 and DD4 are not compatible. Make sure you buy the right memory. If you are not sure, ask in a store or online before you buy. What doesn't usually matter as much is the brand. Most computer manufacturers don't make their own memory anyway.

Compatible memory will usually work but occasionally it won't. This happened to me a couple of years ago with a Lenovo Thinkpad.

The computer was constantly close to or actually running out of memory (according to Windows Task Manager) which seriously impacted my productivity. I needed to upgrade the memory quickly so I went over to Staples, purchased some memory and stuck it in my laptop. It worked perfectly on the first shot and was totally reliable.

About 6 months later my laptop got stolen and I replace it with the exact same model. Once again I had to upgrade the memory so I went back to Staples and purchased the exact same part number. My laptop wouldn't start up. I suspected that it was probably just a bad stick so I went back to staples and exchanged it for another of the exact same memory. The new stick didn't work any better. So I returned it. I admit that I was surprised and disappointed, especially since it had worked so well in my previous machine.

This was the first time since way back in the days of 386 CPUs that such a thing happened to me. I've even got great deals purchasing memory off of eBay, knowing full well that I was taking a chance, and they always worked well and were super reliable.

The moral of the story is, wherever you buy your memory, make sure they either have a good return policy or that you are getting a really good deal. The alternative is to get certified Lenovo memory from a place which may not have such a great return policy which is what I ended up doing. It was just a few dollars more and it worked on the first shot.