Micro scandisc 512 MB

You don't say what type it is, but they usually have little micro switches fitted to ensure the power won't come on until the blade section is fitting properly to the waste container part.
If it is the bucket type with the shred part on top just make sure it rests properly on top of the bucket so the microswitch on the bottom of the shred part gets depressed.
If it's a drawer type there may be a small projection on the drawer which pushes against a switch in the body of the shredder.

Make sure access door is closed and latched completely & try pulling power cable for 30 sec then reattach and try restart. If those don't work - contact macsales.com (excellent Apple/Mac folks)

the cruzer u3 with its bells and whistles is a pain in the backside pendrive,
they are cheap now try another

Here are some instructions that should work for all 3000 series laptops.
http://support.gateway.com/s/Manuals/Mobile/8512061_Apache_RPL.pdf

That last RAM probably is good. Many motherboards have problems using many different memory. All of the memory you have should be at least identical to ensure that they work. When RAM run at different speed or require a little more voltage, they will not let your motherboard boot. You can try mixing up the order you put the RAM in. Try putting the last RAM in the first slot by itself, the motherboard should boot. Then try the rest.

Also, whenever you add or change hardwares, you should clear the CMOS/BIOS settings.

According to Motorola 512 mb cards are the largest you can use in this phone without problems

It might be broken.. Buy a new one here http://www.dealextreme.com/details.dx/sku.23756 It's free shipping worldwide, the usb pen is 1 Gb (twice the storage you have now) and costs $6.

remove ur memory card and format it with help of pc . then reinsert it in your phone and formar it again it will definitely work

It wont work, it will hang ur system. Ur motherboard supports but using Mutli-frequencies RAM is not possible, either u use SDRAM 512 BM PC133 or ur 64/128 PC100 RAM, You cant use all together.