Looking for advice about a possible GPU purchase

The 9800GX2 is a dual GPU card from about 4 years ago. In terms of raw power it is still quite potent, sitting in the same tier as the Radeon HD 6850 and the GTX 460. However it has no DX11 support, and since it is dual GPU you may not get full performance out of the card with every title. Titles that have issues with SLI won't perform as well, though it should still give you better performance than your 2600 XT, even with only one GPU working.

There is a good chance that you will run into a CPU bottleneck if you do get the card, a C2D at 2.33GHz is probably not going to be able to keep up with it, especially in Skyrim, which is very much CPU bound. Since this is a prebuilt computer from Dell, overclocking probably isn't an option, as those options tend to be locked out on prebuilt systems.

80 Euros isn't a bad price for a card at that performance level, though perhaps a bit high for a really old card that has been used. You'll want to research Skyrim and make sure that it supports SLI properly, if it doesn't you'll lose out on a fair bit of performance if your CPU doesn't hold the card back too much. That and given its age, that card may not last you too long, a lot of the 8000 and 9000 series nvidia cards are starting to die at this point, you may not get a good lifespan out of it. You may be better off looking at a more modern card that you can carry over to another build. 80 Euros won't get you as much raw power as a 9800GX2, but you probably won't see full performance out of the 9800GX2 because of your CPU anyway. A newer card would also support more current features, and wouldn't be dual GPU in this price range, so you wouldn't have to worry about SLI support.

If you do go for the 9800GX2 ,you'll want a rather beefy power supply for this card. It's specifications call for 197 Watts maximum draw, with a 580 Watt PSU being nvidia's recommendation. A good quality 550 Watt unit will do the trick, Antec, Seasonic, Corsair, Enermax, PC Power and Cooling are good brands.

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Supernova1138 is very knowledgeable when it comes to GPU's Old and new. His advise is well worth reading and following. In plane simple terms He know's what he is talking about.

I have had 3 prebuilt rigs 2 dell and 1 compq. My last one the Dell insriration 580 with the i3 cpu 6gb ram and 300w PSU. My first GPU was a GT 220 and I burned it up. My second one is a GT430 and when I let my son play some the top games today on it major problems.

My point to all this I got tired of problems and desided to build one and now I can play just about any game out there. I would have been able to play on max but I bought the wrong GPU's. This is just food for thought. Anyway I wish you the best of luck.

thanks very much for the advice guys, exactly what I was looking for. good to know the limiting factors with my computer. the only reason I'd be getting the 9800GX2 would be if it was very very good value for money, which it seems it isn't at this point.

So, if I was to go for a more "future friendly" computer upgrade, I should really be upgrading cpu, gpu, and power supply all at once? What would you reccommend?

I don't have any exact spending criteria since I don't know how much these individual parts cost in general, but i'd go for value for money over anything else.

Nothing too new/fancy/expensive, probably slightly cheaper, slightly dated stuff that would stand the test of time and really beef up my computer

Cooler Master GX 450W '80 Plus' Power Supply
Radeon 5770

To get a CPU upgrade you'll probably need to upgrade to a new motherboard, and get new RAM as well. Your current board may support a better C2D, but the better C2Ds are quite expensive now, as they are getting rare but demand is still somewhat high.

A more budget oriented gaming build would be something along the lines of a Sandy Bridge Core i3, a mobo based off the z68 chipset, and 4GB of DDR3 RAM. That will be much faster than your C2D, and the z68 boards will take the upcoming Ivy Bridge CPUs. You may want to consider a Gen 3 board if you want to have PCI-E 3.0 support for the future.

AMD is a bit cheaper, but there is no real upgrade path right now for gaming, Phenom II X4 is as good as it gets for gaming from AMD. Unless AMD manages to fix the flaws in their current CPUs single threaded performance, they're not going to be the greatest for gaming, though the Phenom IIs are still okay for now.

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Again he his right. If the third Gen MOBO's are able to support the second Gen CPU's then go for it. Plan for the fucture.