Help. Swapping pre-built parts into a new case

[saab93]

Sorry if this is in the wrong place wasnt sure where to put this.

I am looking to upgrade my video card in my pre built hp a6152n to an ati hd 4850. Now the hp case is a little small and im worried about the card overheating. I already have a larger case. I will also have to upgrade the psu and finding one that would fit in the hp case would be hard as well. So i was wondering if swapping all the hp parts into another case would be a probelm. Also would overclocking the q6600 be possible in a larger case due to not as many heat issues. Just to tell you, everything is crammed pretty tightly in there.

Specifications
Processor: Intel Core 2 Quad Q6600 (2.4 GHz, 1066 MHz front side bus)
Memory: 3GB (Maximum allowed: 8GB (4 x 2 GB) (64-bit OS), 4GB (4 x 1 GB) (32-bit OS))
Hard drive: 400 GB SATA 3G (3.0 Gb/sec) 7200 RPM
Optical Drive: 16X DVD(+/-)R/RW 12X RAM (+/-)R DL LightScribe SATA drive
Modem: 56K bps data/fax modem
Video Graphics: Integrated graphics
Sound/Audio: Integrated High Definition audio
Network (LAN): Integrated 10/100/1000 Base-T networking interface
Operating System: Windows Vista Home Premium
Refurbished: 90 Day Warranty
I/O ports
1 x 15-in-1 card reader
2 x 1394
6 x USB
1 each x Headphone, Microphone, Line-In (Front)
2 x PS2 (keyboard, mouse)
1 x VGA
1 x LAN
1 x SPDIF out (coaxial)
1 x SPDIF in
1 each x Audio (side speaker out, rear speaker out, center speaker out, line-in, line-out, microphone)
Expansion slots
1 x PCI (None available)
1 x PCI Express x16 (One available)
2 x PCI x1 (Two available)
Drive bays
2 x 5.25" (One available)
2 x 3.5" (One available)
1 x Pocket Media Drive (One available

Do You guys think i even need to switch the case in the first place?

The case i have is pretty old but i dont think that would be a problem.

Thanks so much for your help as I am a noob when it comes to fixing computers.

 

[auscanzukus]

The mobo does have a PCI-E slot, so the HD4850 will fit.

http://h10025.www1.hp.com/ewfrf/wc/document?docname=c01077641&lc=en&cc=ca&lang=en&product=3445434&dlc=en

Can you confirm the psu is 300W? Look at the side label on the psu. How many amps on +12Vs? Also, does it have a 6-pin PCI-E connector? ATI recommends 450W:

http://h10025.www1.hp.com/ewfrf/wc/document?docname=c01077641&lc=en&cc=ca&lang=en&product=3445434&dlc=en

http://ati.amd.com/products/radeonhd4800/requirements.html

You can pick up a 500W that can power even the HD 4870 in case you upgrade to that later on. Look into Corsair.

 

[zeroyb]

Switching to a bigger (I'm assuming with better air flow) case will be worth it if you can make everything fit. Also, manufacturers like HP and Dell use custom parts so your computer might look a little funny when you're finished or have some mismatching colors. Finally, make sure everything is removable before you start! I've seen them bolt components such as hard drive from the inside, making it impossible to remove unless you literally disassembled the whole case. Except for well-known parts like video cards, those manufacturers tend to make their computers unfriendly to upgradeable components. And if you have the original PSU that PC came with (which is most likely cheap and supply barely enough juice), I'd highly recommend replacing PSU when upgrading video card as auscanzukus suggested.