Graphics upgrade on a desktop. Need some help :)

Hi every one ! 

   I want to upgrade my desktop, to have better graphics.

Here is my specs:
 - Gateway LX6810-01 [Here is a link for all specs (my RAM is different than the webpage) : http://reviews.cnet.com/desktops/gateway-lx-6810-01/4507-3118_7-33513654.html]
 - CPU: Intel Core 2 Quad Q8200 2.33GHz (socket 775 LGA 45nm)
 - RAM: 2GB DRR2 PC2-6400 400MHz [Virtual: 4GB]
 - Motherboard: Gateway FMCP7AM [Chipset nVidia nForce 730i PCI]
 - GPU: nVidia GeForce GT120 - 1GB GDDR2 PCI Express x16 (Average idle temperature 66 deg C)

Actually I would like to upgrade to the GDDR5, and DDR3... But is it possible with my motherboard?
I want to get a better FPS on the latest games

And at the same time, I'm making research on how hardware is compatible, and any advise would be really appreciated.
I'm looking to upgrade with something good, and relatively at a good pricing

Thank's for all of you ! 

Get 2GB more RAM, You'll notice an imrovement there right away.

Get 2GB more RAM, You'll notice an imrovement there right away.

/Agree

The other thing to look at is the PSU. According to your link you have a 400W PSU which is very borderline for a mid-high range PCI-e card, any may or may not have the applicable PCI-e power connector. (6 or 8 pin)

You would need to find out what connectors it has and the Amp ratings on the 12V rails (Usually printed on a sticker on the side.

As for upgrading to DDR3 RAM you will need a new motherboard that supports it. Yours supports DDR2 only and the spec sheet for it linked says you have 1 slot total with one free  so it is very difficult to determine how much RAM you can actually install into the machine. The graphics card carries its own RAM controller so a GDDR5 graphics card will run just fine, with enough power from the PSU of course 

Ok,
So I have to get an extra 2GB RAM, but only DDR2 is compatible.

And how about an nVidia Geforce GT440.... that's the cheapest 1GB DDR5 I've found

But doing that... is it going to improve my gaming performances a lot? or just a little bit ?

And according to that Power Supply calculator, I need a 650W
http://support.asus.com/powersupply.aspx

Does it sounds right ?

I'm thinking about this 4GB PC2-6400 DDR2 RAM
http://www.ebay.com/itm/NEW-4GB-4x1GB-Memory-Dell-Inspiron-530-PC2-6400-DDR2-/300544221398?pt=LH_DefaultDomain_0&hash=item45f9d4e0d6
[By the way: Do I have to get only PC2-6400 ram?]

Or this 2GB DDR2 RAM PC2-6400
http://www.ebay.com/itm/2GB-DDR2-PC2-6400-PC6400-LOW-DENSITY-240-pin-800Mhz-RAM-/330600730953?pt=LH_DefaultDomain_0&hash=item4cf956d149

And this graphic card nVidia GeForce GT440 1GB GDDR5
http://www.ebay.com/itm/Asus-nVidia-GeForce-GT440-1GB-DDR5-VGA-DVI-HDMI-PCI-Express-Video-Card-/380380645484?pt=PCC_Video_TV_Cards&hash=item589074086c
[Do you know any graphic card with 1GB DDR5 cheaper than this one?]

+a 650W power supply

You would need to find out what connectors it has and the Amp ratings on the 12V rails (Usually printed on a sticker on the side.

On the motherboard there is a 4 pin 12v connector.
I've found some 650W power supplies with the same connectors. But you are talking about the amp...
What do I have to look for? Do I have to check the amp that motherboard needs, and compare it to the power supply?

Thank you a lot for your help! 

Your videocard runs way too hot, you'll have to invest in better cooling before buying an even faster videocard. Is there a fan blowing air in and out of the case?

Judging from Google images, there aren't.

Your videocard runs way too hot, you'll have to invest in better cooling before buying an even faster videocard. Is there a fan blowing air in and out of the case?

Judging from Google images, there aren't.

There is not...
Only a CPU Fan... and the graphic card has it's own small mounted Fan on the card.

But there is no FAN blowing air in and out of the case...

Yours supports DDR2 only and the spec sheet for it linked says you have 1 slot total with one free  so it is very difficult to determine how much RAM you can actually install into the machine

There is 4 Slots on the motherboard for the RAM, two are yellow, and two are blue,

For now I have only one 2Gb RAM stick

By the way, why are they colored like that? (Two by two) ?

That's most likely a Dual Channel designator. Put two identical sticks in the similarly coloured slots and you'll enable dual channel.
If you put RAM in the other slot, it'll disable dual channel mode. Although it might turn it back on if all four RAM sticks are identical.

Could also be to let the user know that one slot accepts a different type of memory but the former is much more likely. Can't find your mainboard manual so I can't verify this.

You should get to installing one fan that blows air out (from the back) and one fan that blows air in (the front). That should lower case temperature and increase hardware longevity and stability. It's an absolute minimum requirement for any gaming machine.

Once that is done, you should make sure the PSU is capable of handling the videocard you planned on installing.
The GT440 will no doubt give you a performance boost.

I'd go with AMD/ATI, personally. XFX has an excellent line of videocards.

I'd go with AMD/ATI, personally. XFX has an excellent line of videocards.

Which one would you recommend ?

I want to go 1Gb DDR5, or keep mine.... (Is it a good idea?)

About the 66 deg C idle temperature: an extra FAN would lower that temperature ?

and would a 650W PSU enough?

It will most likely save a few degrees. Especially during warm days. There's almost no air flow in and out of your case except for what goes through the PSU. And that shouldn't have to cool the rest of the system.

I think the HD 6770 would be a good budget gaming card. It's up-to-date and it's DirectX11 ready. Which your current card is not.
Whether that is important is up to you and your gaming habits.

I still use a 5770 and it suits pretty much all my gaming needs.

650W should be enough. You can calculate wattage usage here: http://extreme.outervision.com/psucalculatorlite.jsp
Make certain it has the right connectors for the videocard as mentioned before.

Make certain it has the right connectors for the videocard as mentioned before.

Ok, But I'm looking online... And where can I find what connector is on the graphic card?
For example here is a good AD that gives many specs about the card... but where is the connector?
http://www.ebay.com/itm/NEW-XFX-HD677XZNLC-ATI-Radeon-HD-6770-1GB-GDDR5-PCI-E-2-/150735111000?pt=PCC_Video_TV_Cards&hash=item2318834358

Requirements
External Power - 6-Pins:1
Minimum Power Supply Requirement:500 Watt
XFX Recommended Power Supply:XFX 550W PSU

http://xfxforce.com/en-us/Products/Graphics-Cards/ATI/AMD-Radeon-HD-6000-Series/AMD-Radeon-HD-6770.aspx

XFX has different versions of the same card. Some come with different connectors than others, make sure that you're taking the one that you need for your monitor set up. The one you have chosen seems to have one DVI, one VGA and no HDMI.