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Why does my computer crash after adding RAM?


My nephew has upgraded his computer’s RAM from 256MB to 512MB. It operates
much faster and the system recognized it fine. But after launching his browser
the system freezes up. It does not do this with 256MB. His computer has 2 slots
capable of 256MB max for each. We have since purchased an additional new one to
match the other but the problem still exists. He added a 128MB chip to the open
slot and no problem, it reads 384MB. We performed a full factory restore, same
problem. We’re both scratching our heads on this one. I’ve assisted many family
members with memory upgrades and never a problem. Any ideas or suggestions
would be greatly appreciated.

Adding RAM is one of the most cost effective ways to improve your computer’s
speed and overall efficiency. Windows loves RAM.

Except, of course, when it doesn’t work.

I’ll look at some of the issues to consider when adding RAM, and of course
what I think has happened in this specific case.


Bad RAM.

The symptoms you describe are more than likely due to a bad RAM chip, particularly in an older machine. I’d replace it with another of the same size, and it’s likely that the problem will go away.

“Bad or mismatched RAM is the most likely cause, by far.”

If you’re so motivated, you might consider running a memory test program such as the free download version of Memtest86. I’m guessing that running that for a while will indicate that there’s a problem with the particular chip you’re attempting to add.

Another possibility is mismatched RAM, or RAM of inferior quality. Even if you get the correct size of RAM chip – in both the physical and capacity sense – there may be other factors at play such as the required bus speed. Getting a RAM chip that is rated slower than your computer’s memory access or “Front-side bus” (FSB) speed could cause the types of problems you’re seeing as well. (Crucial has a good overview of memory speeds and compatibility.)

Making sure that you get the correct memory for your system is important. With so many options it’s very easy to get confused. Even if you don’t purchase from them (though I do), Crucial specializes in memory upgrades and has a very good analysis tool that you can download which will tell you exactly what you have, and what upgrades are available to you.

Bad or mismatched RAM is the most likely cause, by far. Windows itself should easily and transparently handle 512 Megabytes – I wouldn’t expect a reinstall, for example, to have any effect on this type of problem. There are rare cases where a motherboard or other device on the system could somehow be sensitive to certain memory ranges, but … well, like I said, it would be very unlikely.

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16 comments on “Why does my computer crash after adding RAM?”

  1. Leo, I think you mean you WOULDN’T expect a reinstall to have any effect on this type of problem, right?

    Whoops. Very true – corrected in the article. Thanks for catching that.

    – Leo

  2. You might want to check the BIOS FSB and memory timing settings. How adjustable these are depends on the particular BIOS, but the BIOS of many machines allows the user to set processor, FSB and memory speed for overclocking. The problem may be that memory is overclocked (can even come that way from the manufacturer), and the new memory chip can’t handle it. Usually, a BIOS has a “safe mode” option, which sets BIOS timing values so that there shouldn’t be issues – you might want to try that first to see if this fixes the problem. Otherwise, go with MEMTEST86+, as previously mentioned, and do the test one chip at a time to isolate the bad memory chip.

  3. I had memory problems after building a PC but when I emailed the company they told me the voltage in my bios had to be change. Once changed no problems.

  4. Similar problem: I bought two 2G sticks for Lenovo box. They will not work together, but work flawlessly alone or with a 1G stick. The MB has only two slots, so the maximum I can get to work is 3G. I got a video card with 1G memory. Is it true that 32 bit Vista, with a 4G max, would only recognize 3G RAM anyway, with a 1G video card?

  5. It is more or less true Windows will only recognise 3GB, if it is 32 bit it can address 2^32 ie 4GB RAM but some is taken up for other uses aside from graphics. For example, I have a 256MB card and 4GB RAM and Windows only reports 3327MB. However, if you use matched memory modules they can operate in dual channel mode which is faster.

  6. I tried upgrading my friends DaeWoo CT6560-cady1 with 2 x 256MB RAM and with one or the other in either slot the machine works but put both in and windows XP freaks out with a STOP: 0x00000005 error, telling me to do this and that and to press “F7” while installing windows, I’m not installing windows, it’s been installed for over 5 years now, the RAM isn’t bad I’ve tested both one at a time in both slots but only one at a time will allow windows to boot, put 2 in and it hangs take either one out and it starts up

  7. I had the same problem. I Took the new 512 stick out & no problems. I Have now brought a new stick & all is going fine.

  8. On another note, if you are reasonably sure that it is bad ram and you bought it new, be sure to look into warranties (always save the packaging). I had a similar issue with some Kingston ram. One of the two chips I bought didn’t work. I called customer service and they replaced the bad chip for free with minimal hassle. It pays to check on that before you go out and buy another chip.

  9. my computer was absolutely buggered crashing and screen not coming on about everything tht cud go wrong did then i took a ram chip out and it worked perfect. I got a hold of another and added tht it worked fine then one day it decided to act up again so i took the ram out, and tho very slow worked fine again, when i tried to put in new ram just a minute ago it loaded onto windows then frooze at desktop i had to turn off at wall as button wouldnt respond then take ram out now so is it a problem with my ram ports, bios, chips, or is my computer just a pile of crap with a very tyred hamster running in its wheel trying to get my comp going. When I got this pc the only prob was it had no ram the processors 2.8 ghz good mother board average video card etc so why cant it handle sum decent ram?

  10. Just to add my piece-
    IBM T20 ThinkPad, stable but too much use of the swapfile with 2x 128Mb modules.
    Changed them for 2x 256Mb modules, Windows crashed after a while.
    Supplier changed the modules, Windows still crashed, even after full re-install.
    Ran Microsoft’s memory checker for 48 hours continuous, not one error.
    Back to the 2x 128, stable again.
    more info-
    One 128 module is IBM (Hyundai chips) & the other 128 module is Corsair (Micron Technology chips).
    First pair of 256 modules had Samsung chips, second pair are Buffalo chips.

  11. I have a similar problem. My windows xp BenQ 2100 laptop came with 512 mb (256 + 256) RAM. I upgraded it to 2GB (1 + 1 GB) RAM. My computer worked like a breeze:) A few months later my laptop crashed due to unkown causes. I had to re-install XP which formatted C. Then 2 GB no longer worked. It only works on my old 512 RAM. I hope this sequence that I have listed here may shed more light on RAM related windows issues. Thanks-a-heap for any further inputs :)

  12. Ordered more RAM from Crucial and I ordered the wrong size. They gave me an RMA # no problem and let me order the correct size.

  13. Simple yet effective article….I have a XP system (SP3) which was working just fine till I decided to double its RAM form 512MB (free RAM was 130MB) to 1GB. Both RAM modules were physically and otherwise similar (though of different manufaturers). My system now just restarts suddenly when I’m surfing. This happens after sometime has elapsed since I start working on the comp. In 24 hours, this has happened thrice. Although it may not be an alarming number, I always like to know the reason why its happening at all. Please help !!!

  14. I have had the same issues with a Toshiba Tecra 8200 older model.I installed a 256Mb into slot A to upgrade from,and, my system locked up also! Since then I have taken Leo’s advice! So,now I am awaiting my new memory stick…Lord willing all will go well for me too.MA.


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