Need help making a decision...

So, lets just get to it; Today, when turning on my computer, as I turned it on, all I got was continuous short beeps. According to some research, either my power supply is bad, my motherboard, or a combination of things. Granted, I was cleaning it before hand, and might've done something, but that aside, some parts of the computer are old as hell, so I was planning to change these parts anyways.

So, just asking, should I just try and fix what I got, and if not, anyone have a good idea what I could get to replace the power supply, motherboard, and probably the CPU for about 200-300 dollars? I'm not familiar with these, since I've usually just changed the video card, RAM, or hard drive.

I mostly use it for gaming, and some programming.

Current build:
AMD Athlon 64 x2 Dual Core Processor 6000+ (want to upgrade)
NVidia GeForce 9500 GT
Two Gigs RAM
ECS MCP61P-AM Motherboard (want to upgrade)
Delta 400 Watt Power Supply (want to upgrade?)

Could you tell us how many beeps it makes? Could be your videocard or RAM are not properly seated, so you could try removing and reinserting them in their sockets and see if that helps.

Listen for the quantity and frequency of the beeps and check your motherboard manual.

"Today, when turning on my computer, as I turned it on, all I got was continuous short beeps."

By continuous, I mean it keeps going. By short, I mean less then a second long.

@Speed: I did, and it said that there was probably something wrong with the power supply, or system board (motherboard).

I have already checked the seating of the video card, ram, and other components on the unit.

I just read you have an unbranded PSU. Pretty likely to be that.

That's what I figured it might've been. Like I said, some parts are old, and need to be changed anyways. Any suggests on what I should get?

if it was PSU, most likely it would not beep at all, due to lack of power.

Does your GPU have external power? My 8800GTX makes me know that it's not plugged in with it's siren like alarm.

Double check that perhaps.

My GPU is inserted properly, and working fine, by the looks of it.