I've been trying to upgrade my system memory and have had no success.First of all, I have (2) 512MB memory modules installed and am trying to increase it to 2 Gig total. When I add the 1 Gig,(only have 3 memory slots), FS locks my computer so that I have to kill the power to restart. All 3 FS, 2002, 2004, and FSX do it. All work ok if I use 1.5 Gigs (1 Gig plus 1 512mb).The other weird thing is that anytime I have the 1 Gig module installed, either by it self or in combination with the other 2, the computer will only boot up if it is cold. If I turn it off and try to reboot, I get a series of long beeps and nothing come up on the monitor. Let it cool down for about 15 minutes and it will boot ok.I don't have a cooling problem and my system is not running hot. Also, no overclocking involved. I can warm reboot ok.According to my motherboard specs. it can handle up to 3 Gigs total.Don't know if my new 1 Gig module is bad or what. Can't figure why FS locks my system up if I have the 2 Gigs installed. Everything else on the computer works ok - just not any FS.Sure need some advice on this one. Thanks.Jim

Rather than start a new topic to repeat the same information, check out the other thread we've already got running about RAM, as the answers there will be the same.Allcott

I stand corrected. Sorry to have wasted your time.Jim

Hi Jim, problem solved? If not, pls indicate mainboard/chipset details. Rgds Jaap

Hi Jaap,No, the problem still exists. I am sending the 1 Gig module back and getting a replacement. Don't know what else to do. I even contacted my computer manufacturer and was told to go into my bios and select "top performance". Did that but did not fix the problem.The thing that really puzzles me is that those times that the computer will boot with 2 Gigs, why will none of my FS load and then lock up my computer? Oh well, I'll just wait on the new module and see what happens.Jim

Hi Jim, it could be your mainboard (chipset) is playing up on you? Is your board ok with 3pcs double-rank modules? Intel's i845PE for example supports max 2 such modules (despite havindg 3 RAM-slots). I hope the replacement works. Good luck and kind regards Jaap