Not sure whether someone is still interested in upgrading the RAM on 2510.
I've just upgraded mine to 4 GIGs! Both Bios and Windows 7 x64 bit have recognized them properly, but it turned out that audio device is not working (just not seen in the system) and the screen shows white stripes all over the screen on logon and shutdown. Everything else was perfect. The system was like a Jumbo jet. So I just took off one of the 2 gigs ram slots and everything started working fine. I didn't try a fresh installation of Windows or Linux on 4 gigs, so, I'll probably give an update later on it, but I suppose the result will be the same. The motherboard bus and the processor just can't handle that much.
The information that I'll give below is FYI only. If you decide to follow my steps, please note that you do it at your own risk.
"Where is the 2nd slot?" many will ask. It's on the opposite side of the motherboard.
I have faced several problems with my amilo (like a failed ethernet port, sound problems, video problems, etc. Unfortunately, technical support for Fujitsu in my country is awful, so I have decided to take a screw-driver and decompile my amilo to the last piece. In general, one can unscrew all the screws on the outter cover, take it off, then unplug all the wires off the motherboard, take off the cooler and the processor, HD, etc - the motherboard will release smoothly. turn it around and you will see the second slot for the RAM.
Actually, there is a way to get to the second slot from atop of amilo. There are plastic jacks under the keyboard (like on Dells) that will let you just take off the keyboard and get to a single screw that will open the cover of the second slot. I have not figured out how to take the keyboard off, so I went a long way from it's bottom.
And I'm still not sure whether 4 gigs is actually possible for this system.