upgrading graphics card.

[deathville]

You won't need more fans cause you're getting a new psu, you don't even need a new one. You've got a 500w psu, of who knows what quality, but you should be able to power something like a 5750 no problem.

Newegg.com - SAPPHIRE 100284L Radeon HD 5750 1GB 128-bit GDDR5 PCI Express 2.0 x16 HDCP Ready CrossFireX Support Video Card - Desktop Graphics / Video Cards

Actually, its only 400w. Ignore the link if it said 500w.

So am I able to run two gfx cards at the same time?

 

[deathville]

Well I opened my PC up, And next to the gfx card there's definitely a slot where I can put another gfx card in. So what do I do? Do I just install it and I'm good to go?

 

[patonb]

No, those are just PCI spots....

According to your link, you have a nvidia 720 chipset, so its only 1 pci-e x16 slot

 

[deathville]

No I think it says I have 1 add-in slot, which is in addition to the current slot.

 

[Muffin Man]

add-in doesn't mean, "in addition to".

your mobo only has 1 pcie x16, 1 pcie x1 and 2 pci slots, so no, you cannot run 2 gfx cards.

 

[Apokalipse]

Get a 5750, use that as the primary card.

Then you have the option of using the GT 120 as a PhysX card (though I'm not sure it would give you great performance in games that use PhysX)

 

[deathville]

add-in doesn't mean, "in addition to".

your mobo only has 1 pcie x16, 1 pcie x1 and 2 pci slots, so no, you cannot run 2 gfx cards.

Get a 5750, use that as the primary card.

Then you have the option of using the GT 120 as a PhysX card (though I'm not sure it would give you great performance in games that use PhysX)

Well I have a nvidia chipset, so I'd still prefer sticking with nvidia (just as someone else said, I feel iffy mixing the two up, even though it says they're compatible )

What would be a good card which is substantially better than my current card (and would still be powered by my 400W PSU).

 

[deathville]

How do these ones look? (In relation to my current card, the GT120)

Newegg.ca - EVGA 512-P3-N871-AR GeForce 9800 GTX+ 512MB 256-bit DDR3 PCI Express 2.0 x16 HDCP Ready SLI Support Video Card - Desktop Graphics / Video Cards

Newegg.ca - PNY VCG98GTXPXPB GeForce 9800 GTX+ 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready SLI Support Video Card - Desktop Graphics / Video Cards

 

[Muffin Man]

either of those would require a psu upgrade.

 

[Apokalipse]

Well I have a nvidia chipset, so I'd still prefer sticking with nvidia (just as someone else said, I feel iffy mixing the two up, even though it says they're compatible )

The chipset brand is irrelevant. The only difference it makes is the fact that it can run SLI, and not crossfire.
Also, I used to run Nforce4 and Nforce 590 chipsets. It's a silly myth that ATI cards would have issues on them.

One of the best things about the 5750 is that it doesn't use much power at all.