Dell Deminsion 4700 won't boot

Hi, Brand new here and this is my first post.

I have a Dell Deminson 4700 that won't boot and here is some background:

Found two leaking Caps on motherboard yet system was running fine; later it blued screened and wouldn't power on after being shutdown.

- ordered new motherboard, transfered CPU and RAM to new board and installed--No Change, system still wouldn't power on

- Installed brand new PSU -- No Change

Diag Indicators:
- Power LED changes
-- Sometimes steady amber; sometimes blank
-Diag LEDs
-- Sometimes "A", "C", "D" = Green, "B" = blank/Amber; sometimes all are blank

- Beeps
-- No beeps

I have tried disconnecting all drives, RAM and installing one at a time--still No change, system won't power on.

Can anyone help me find a fix? :cry

 

No Hard drive spin up
fans start but stop very quickly
double checked connections
Yes I was grounded with wrist strap
Cleaned heat sink and added new paste
Double checked CPU position
Double checked RAM seat
Board was not from manufacturer but is same model

 

I know this is very basic, but, is the bottom of the motherboard touching the case? Lots of boards come with "separators", plastic things you put between the case and the board when you install the motherboard, to prevent shorts. If the board is good, no matter the HDD condition you should still get a POST of some kind.

 

All thanks for the replies, sorry I have not been able to respond quickly..something called work and full load of on-line college classes tends to slow me down at times.

Mimsy--I checked and there are no plastic or rubber separators; there were not any with the original MB either

Digitallocksmith -- (peculiar name there ) NO problem with the questions (thats why I'm here to make sure I have not forgotten anything), here is what I get:
---both PSU and CPU fans are spinning
---Can't tell if HDD is spinning up
--- NO BEEP CODES; this is what has me most concerned

:confused

 

Two or more minds r better than one

 

Okay, this is where I suggest my all-time favorite solution to all hardware problems: Have you checked the PSU? Just because the fan comes on doesn't mean everything is okay with it...

 

Yep PSU is good I even replaced it just in case still no help

 

Last time I saw a system with a working PSU and no beep codes, the CPU was bad... that would suck. Do you get error beeps if you remove the RAM? That would indicate it makes it past the CPU through POSTesting.