First time upgrading my PC, need help

[Rovescio]

My PC is a Gateway DX4860, with fairly good specs (Intel Core i5 @ 3.00 Ghz, 8GB RAM, 1TB HDD), except for the GPU, an ATI Radeon HD 7350 which I think is a 5450 refurbished. I already have my eyes set on the GTX 650 Ti for I have a tight budget. Since it's my first time upgrading and I have little knowledge, I have many questions:

1. Will the new GPU fit into my case? Also, according to this:

http://www.techpowerup.com/gpudb/632/AMD_Radeon_HD_7350.html

and this :

http://www.legitreviews.com/images/reviews/2052/gtx650ti-cards.jpg

the GTX 650 Ti has different input slots comparing to the 7350.

2. Which brand should I get? There's EVGA, ZOTAC, Gygabite and ASUS. What's the difference between them?

3. Will I need to change the PSU? I think my PC has a power supply of 300W. Is the PSU a device that goes inside the case? Where is it situated exactly? (like I said, I have little knowledge... )

4. Is this the best deal I can get with a budget of maximum $160?

Thank you in advance!

 

[DarklamaR]

1. Fits 100%
2. Different clocks, fan/heatsinks. complectation.
3. 300W? No way. Your power cable inserted in PSU =)
4. Not bad, but you should look at 7850 too.

 

[bigshootr8]

You have the clearance for a 2 slot card yes. There is another thread with a person using the same computer as you. It's very hard to tell based on Gateway's information what your power supply is rated at if you could open up your case and maybe take a look and post here what the real information for the PSU is that would be helpful as well.

An example of where to look on a Power Supply the side Sticker
Things needed to know the wattage of the power supply and the voltage/wattage on the 12v rail.

http://support.gateway.com/s/desktop/2011/gateway/dx/dx4860/dx4860sp2.shtml



http://www.tomshardware.com/forum/268221-29-where-fans

 

[Rovescio]

Hello everyone, thanks for your quick replies

The other night I found these two on the local ad site:

http://www.techpowerup.com/reviews/ASUS/Radeon_HD_6850_Direct_Cu/2.html, completely new, $100.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139021&Tpk=tx%20750, also new, $70.

Are these two a good choice? For a total of $170 I think it's pretty beneficial. According to this my PC is a mid-tower case, so should a 6850 (10.24" x 4.84") fit? I think I'll have to measure it myself.

Please let me know if it's good. Thank you!