Computer part upgrades

[eeveez]

Hi first time here hopefully this goes here if not I'm sorry. anyways thanks for your time.

I have a HP Compaq DC7900 CMT(convertible minitower) that i wish to upgrade or max out this old pc's potential :

Stock:
CPU: intel e8400 Core 2 Duo @ 3.0Ghz
PSU:365W
GPU: Radeon HD 2400 256mb
RAM: 4-GB DDR2 Synch Dram PC2-6400 (800-MHz) Non ECC (2 x 2GB)

Using this PDF

My plan so far is to get an
intel Q9650 quad core @ 3.0Ghz cpu
8GB (x2 2GB)
gpu not sure right now

I'm very new to this and have some basic understanding but these are my concerns
will the stock cpu fan work with this upgraded cpu or i will need to get a better fan?
will i need a new power supply also?
I'm open for any suggestions on these upgrades.

 

[spp85]

Intel Q9650 comes with its own cooler which you can use.

 

[kenrivers]

Is your OS (Windows?) 32 bit or 64 bit? If it is 32 bit then it won't support 8GB of RAM. If it is the 64 bit version then go for the 8GB upgrade. Depending on the graphics card you choose you may want to consider upgrading the power supply unit (PSU). My experience with previous HP desktops is that the stock PSU is weak and so is the included graphics card.

 

[eeveez]

Is your OS (Windows?) 32 bit or 64 bit? If it is 32 bit then it won't support 8GB of RAM. If it is the 64 bit version then go for the 8GB upgrade. Depending on the graphics card you choose you may want to consider upgrading the power supply unit (PSU). My experience with previous HP desktops is that the stock PSU is weak and so is the included graphics card.

I plan to install Windows 7 Professional (64-bit) thanks for info on the system type 4GB limit on the 32bit.
for the GPU i might get a ATI Radeon HD 3650 512mb (KS505AA) or if there is better options i don't mind upgrading the power supply.

@spp85 i plan on getting a used one from ebay around 100$ or so it doesn't come with a cooler will the stock work?