So, a friend at work approached me and wanted to know what to do, because he just discovered that his Windows XP expires in April. He didn't know if he should throw his computer away, or what, because he doesn't want to buy a whole new one. He wanted me to guide him in the right direction. My first response is upgrade operating system....obviously. Upon further questioning, he said it was at least 6 years old. Today he finally brought me the model number: a Dell XPS 400. My research reveals the following: It's not limited to proprietary PSU's, and has an open back, so the at least 7 year-old Dell PSU can be tossed for a new one with on/off switch; It can take 4x1GB RAM (he's working with 1 now); It's SATA II, so even at that speed an SSD will benefit him; It has a 6800GTX video card (I didn't even know it came in PCIe version!) running on PCIe 1.0; and it has a Pentium D 820 or 840 in it. So, after reviewing the specs of the 945P motherboard, I think I've devised a cheap upgrade that should net him a couple more years of life out of it and see it's peppiness improve quite a bit. I have an EVGA 9800GT 512MB Akimbo lying around. That needs 26 amps on the 12v rail, thus the need to replace the aged PSU which is 375 watts and puts out 30 amps on 12v rail. The other parts I propose are as follows: Crucial DDR2-667 RAM (2 kits of 2x1GB), because that's the maximum speed, and it takes a max of 4x1GB http://www.amazon.com/Upgrade-Dimension-System-PC2-5300-NON-ECC/dp/B001V6YDMS/ref=sr_1_6?s=pc&ie=UTF8&qid=1393461595&sr=1-6&keywords=ddr2 pc2-5300 xps 400 A Crucial M500 120GB SSD for OS ( He can use his HDD for storage, and the SSD should still benefit system at SATA II http://www.amazon.com/dp/B00BQ4F9ZA/?tag=tec06d-20 And a Seasonic PSU that should deliver clean power, and more of it. This however, is the part I'm most unsure about in that system. http://www.newegg.com/Product/Product.aspx?Item=N82E16817151124&ignorebbr=1 Grand total of $210.00, which is under the $250 he doesn't want to exceed. I'm thinking, depending on the dimensions of the inside of the BTX style case, I may want to recommend him an aftermarket cpu cooler as well for that hot-running Pentium D. I'm looking for an assessment of these ideas and the feasibility of the parts. Any thoughts or ideas are welcome! EDIT: I'm probably going to recommend W7 for him, since he says he is scared of the new W8, and is comfortable with the W7 we use at work. Question: Because he is limited to 4 GB RAM, would he still benefit from 64 bit version, or should I just have him get 32 bit (even though he'd be limited to using 3 GB and change)?