Building PC for first time - won't power on

[Josh1billion]

First off, I don't have much experience in hardware installation, aside from basically installing new hard drives and extra RAM. As a C++ and PHP programmer, I'm more of a software guy. But this week I decided to build a new desktop. I have purchased components for a new PC from Newegg (excluding a case and DVD-RW drive, which I already had). Motherboard, power supply, video card, RAM, hard drive.

After assembling everything, I was greeted with an unhappy surprise: the PC will not power on at all. I have ensured that the power supply switch is on, of course, no luck.

Here is the power supply (Corsair 750W ATX): http://www.newegg.com/Product/Product.aspx?Item=N82E16817139006

And here is the motherboard: http://www.newegg.com/Product/Product.aspx?Item=N82E16813130168

I believe the cause to be that I may have missed a cable somewhere. I have checked and double-checked the cables, but to no avail. Here are the cables I checked from power supply to motherboard; please let me know if I missed any:

- 24-pin cable from PS to MB
- 4-pin connector from PS to MB (power supply is actually an 8-pin connector, but the manual says to "remove" one half if the motherboard is a 4-pin one. So, I plugged the first half of the 8 pins into the 4 pin connection slot - could this area have something to do with it?).
- Power supply jumper cable from case to motherboard

This is very frustrating. I spent ~half an hour or more googling for troubleshooting guides, and couldn't find any solution that seemed to apply except for the cables, which appear correct.

 

[effel]

Did you use the screw standoffs from the motherboard so it isn't touching the case?

 

[fleakiller]

Also do any fans come on?

 

[Josh1billion]

Did you use the screw standoffs from the motherboard so it isn't touching the case?

Yep. They didn't come with the motherboard, they came with the case, but yup I used them.

Also do any fans come on?

Nope, absolutely nothing comes on.

 

[fleakiller]

Did you double check connections for your power/reset switches for the case

 

[Josh1billion]

Yup, forgot to mention that. I did double-check that.

 

[fleakiller]

Well then start with just the mb/cpu/cpu fan pull everything out and see if it will power up

 

[fleakiller]

Also list what cpu,ram and video card you have

 

[Josh1billion]

Video is a GeForce 8800 GS 384mb (PCI-Express).
CPU is an Athlon 64 X2 dual-core @ 2.5ghz.

Could this be a problem with the case? I'm considering the possibility that the case, or particularly its wiring from the power button to the mobo, is possibly broken. I'll see if I can find an old case to test it in. Btw, the only other cases I have are _old_ cases, so are they likely to use different types of power cables from case to mobo (doesn't seem like something that would change, but you never know), and are there any other incompatibilities I should know of?

 

[fleakiller]

Did you remove all but cpu/fan and see if fans come on ??

 

[Josh1billion]

Not yet. I'll also be trying another power supply to see if that's the cause (despite the PS being brand new). Details on that soon...

 

[Josh1billion]

Okay, I unplugged my 750W and plugged in a different power supply, one I bought about a year ago (400W I believe, or else 450W-- much weaker than the brand-new 750W).

And it actually powered on!

However, there was a loud, persistent beep as it was on. I didn't have the temporary 400W power supply plugged into the hard drive, nor the DVD-RW drive, so I'm guessing this may be why there was this beep. Are there any other things that could have caused the beep, or is that most likely it?

So now I have my brand-new 750W power supply that is apparently not working, or else it wasn't plugged in properly.. but I did check and double-check the connections, so I'm betting that the power supply may have been dead on arrival, in which case I'll have to ship it back to Newegg for a replacement.

 

[Josh1billion]

After posting that, I thought to myself, "Wait, why don't I just try it and see?" (in regards to whether the lack of hard drive + CD-RW power was causing the beep)

So I plugged the power supply into the hard drive and CD-RW, and no more beeping. But at the same time, there was a problem: the CPU and case fans were no longer spinning (the fan inside the power supply was spinning, and that was all). My assumption is because this was a 400W power supply unable to power everything. So I will now proceed to plug in the 750W and see if that works now.. somehow..

 

[Josh1billion]

Got it now.

I plugged the 750W into the mobo without HDD & DVD-RW and got the usual beep. I then plugged it into the HDD & DVD-RW and everything powered on successfully. Must have not had a connection plugged in all the way, or something, I dunno.

Either way, it works now. Now, to hook it up to my monitor and keyboard and see if it'll actually be able to install an OS and boot up...

 

[fleakiller]

Good glad you got it going