How would you upgrade this system?

I've been trying to rank improvements to my system in terms of what will give me the most bang for my buck right now. I am trying to determine if upgrading my system will be more cost efficient then building a new one. Chances are building a new one would be better given the age of my system, and its limitations but iI would like to keep this topic to a pure upgrade one. here are details of my current system, any help to determine what to upgrade to get the most performance improvements would be great. I use the system almost exclusively for gaming and web surfing with normal Microsoft office use. I am currently running into issues with being able to run modern games like starcraft 2 and stronghold 3 on even medium graphics.

It is a Dell XPS 400 around 4 years old.

Running 32 bit XP
Pentium D 840 Quad core at 3.20GHz, i945p chipset
3 GB DDR2, all running in single channel since I lack the 4th GB to get all 4 DIMM slots occupied
GeForce 7900 GS 256mb memory
75GB HDD with 10GB free

My thoughts on what to do, please let me know if I am off base...

1.) Upgrading my video card to at least
http://www.newegg.com/Product/Prod [...] 6814127592
MSI N560GTX-M2D1GD5 GeForce GTX 560 (Fermi) 1GB 256-bit GDDR5 PCI Express 2.0 x16 HDCP Ready SLI Support Video Card

2.) Getting a new HD, at least 160GB, probably this one - I'd get a re-certified one for cost savings and the fact that I am looking at just upgrading for about a year while I save money for a better system. I do get a low paged pool memory while playing starcraft 2 often due to not enough hard drive space for memory allocation.
http://www.newegg.com/Product/Prod [...] 6822136898
Western Digital Caviar Blue WD1600AAJB 160GB 7200 RPM 8MB Cache IDE Ultra ATA100 / ATA-6 3.5" Internal Hard Drive -Bare Drive - re-certified

3.) increasing to 4gb DDR2 ram so I benefit from Dual channel.


I think those 3 things would be the best to do for upgrades to the system. Does anyone have anything else they would do? If there is any other info you would like on my current system please let me know.

Save your money. I went through a similar ordeal with a Dell e510 that had very similar specs. I ended up spending around $200 to upgrade the processor, GPU and RAM and I was still left with a system that was slow.

That P4D CPU is killing you and will make upgrading to a GTX 560 completely useless (not to mention you'd probably need a new power supply to even use the new GPU). Similarly, 3GB in XP 32-bit is all the RAM your OS can even recognize. Add to that the fact that dual vs. single channel doesn't make much of any difference and there's really not much point in upgrading the RAM. A new HDD won't help much either, very minimal performance gains to be had there.

Save your money and put together a budget build. For not much more than your planning on spending you could just get a new system that will be worlds faster than your current P4D machine. You might even consider buying another bare bones Dell and just adding a GPU. Even a new Pentium or low end Core i3 will be significantly faster than a P4D.

I wouldn't want to spend more than $250. Ideally anything I upgrade I would like to fold into my new system. Possibly vid card upgrade that could then be put into the new system, something along those lines.

Most likely it will be a new system I get, but I was just looking in case I come across a situation like this later where a new system isn't possible, I am looking to see what would give the biggest overall performance boost.

If your bent on upgrading your machine with a new GPU for now you need to crack open your case and check for two things. One, your power supply's rated wattage. And two, how many 6-pin PCI power connectors you have. These will be your limiting factors when upgrading the GPU if you don't plan on replacing the power supply at the same time. Make sure that whatever you buy will be compatible with your system.

Most newer mid and high end GPU's require two 6-pin power connectors. Low end cards utilize the PCIe slot for power but are severly limited in performance because of this. As a result you won't be playing any new games at high resolution or details.

EDIT: Actually, having just googled your XPS 400, it's identical to the e510 that I had. Your PSU is likely a 350 Watt unit which is underated (good), but it won't have any PCIe power connectors. I think you can replace it with a standard ATX power supply though. Be warned though, slapping a new PSU and a GTX 560 Ti in there won't be the huge upgrade your expecting since the CPU will limit performance. You'll also probably have some case heat issues since the dell case doesn't have much in the way of cooling.