Hello, I have a laptop that had PC100 256 memory in it. Place in some PC133 that I got off ebay and it didn't work. with or without the other PC100 in the laptop. My question is, does the IBM Thinkpad A22m type 2628-DU1 take PC133? or should it at least pop up a bios screen? nothing happens when chip is installed, no beeps, no screen, just the power on light. Any help would be appriciated. Thanks! George Cox Please respond after you have solved your problem to notify who helped you and what solved the problem. Both sides benefit when you do.

http://www.crucial.com Memory has different density etcetcetc, laptops tend to be less tolerent, go to Crucial WebSite and use their Memory Finder to find compatable mem specs...

Thanks Inverto. Crucial says PC133 will work. IBM says only PC100.... conflicting info.... Crucial live tech claim that it works, I beleive them, is it possible to tell if the memory is bad? Thanks! George Please respond after you have solved your problem to notify who helped you and what solved the problem. Both sides benefit when you do.

PC133 may be compatable but is the CS the same: http://www.dewassoc.com/performance/memory/cas_latency.htm

It looks like the samsung brand can have multiple CAS on a single chip. http://www.dewassoc.com/performance/memory/cas_latency.htm It seems that both chips operate at both CAs 2 and 3, just at different Mhz Speeds. they seem to be both CAS 3 for a standard. I have fiddled with the memory a little, and got the laptop to work and recognize all 512, i guess the question is if the computer will acturally run at will any speed. I will have to wait until my hard drive gets in. Then I'll post what I think of the speed. Thanks for all your help! George Please respond after you have solved your problem to notify who helped you and what solved the problem. Both sides benefit when you do.

Well. the computer accepts the two styles and sees them in Bios for the full amount. but windows won't even load, it gets an error message about it. So Looks like the PC133 doesn't work. Please respond after you have solved your problem to notify who helped you and what solved the problem. Both sides benefit when you do.