Dell Precision 670 6 long beeps on post no video but pc is on

what are the indication lights blicking and with which color- amber or blinkking green or solid green

Rear Lights Dell Computer Error Codes

Rear LEDS are labled A through D and can change from green to yellow. Some typical LED reading might be:
A - yellow, B - yellow, C - green, D - green <-- Indicates a problem with the RAM.
A - yellow, B - green, C - yellow, D - green <-- Indicates a problem with the video card.
Refer to the Dell website for your specific model, as these lights can vary from model to model.

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Dell Computer Error Codes

The issue seems to be that your PC can not handle the supported memory. After review of your system specs on dell's website, I see that you're computer would require DDR2 Memory. This seems to be what is causing the beeping. Please check to ensure you are using the correct memory stick. I hope this has helped

Contact technical assistance.They will most likely ask you to send it back to repair.

This chart is where I got my conclusion.

Power Light

Problem Description

Suggested Resolution
Solid green
Power is on, and the computer is operating normally. On the desktop computer, a solid green light indicates a network connection.
No corrective action is required.
Blinking green
The computer is in the suspended state (Microsoft® Windows® 2000 and Windows XP).
Press the power button, move the mouse, or press a key on the keyboard to wake the computer.
Blinks green several times and then turns off
A configuration error exists.
Check the diagnostic lights to see if the specific problem is identified.
Solid yellow
The Dell Diagnostics is running a test, or a device on the system board may be faulty or incorrectly installed.
If the Dell Diagnostics is running, allow the testing to complete.
Check the diagnostic lights to see if the specific problem is identified.
If the computer does not boot, contact Dell for technical assistance.
Blinking yellow
A power supply or system board failure has occurred.
Check the diagnostic lights to see if the specific problem is identified.
Solid green and a beep code during POST
A problem was detected while the BIOS was executing.
See "Beep Codes" for instructions on diagnosing the beep code. Also, check the diagnostic lights to see if the specific problem is identified.
Solid green power light and no beep code and no video during POST
The monitor or the graphics card may be faulty or incorrectly installed.
Check the diagnostic lights to see if the specific problem is identified. See "Video and Monitor Problems" in your Owner's Manual.
Solid green power light and no beep code but the computer locks up during POST
An integrated system board device may be faulty.
Check the diagnostic lights to see if the specific problem is identified. If the problem is not identified, contact Dell for technical assistance.

Verify the light and beep sequence on the back of your computer and then see this link from the Dell support site (scroll down the page) to further interpret and resolve the issue(s).

http://support.dell.com/support/edocs/systems/ws470/en/ug_en/advtrbl.htm

Things to check:

1. Power led on the front of the tower, it should be solid green when on. Flashing Amber is generally an indication of a bad power supply inside the tower
2. Power LED Solid AMBER indicates system is not finishing the power on self test (POST) and you remove all connections from the tower except power and try turning on again. If no change, remove all PCI and PCI-E cards from system, try again, no change replace motherboard.
3. On the back of the tower are 4 diagnostic LEDs near the ps2 ports marked ABCD, after the POST, during a normal boot the will flash in several sequences and with boot is finished all 4 should be green. If they stop an a different pattern, then that indicates a failure Yellow Yellow Green Green indicate bad RAM for example
4. If the LEDs on front and back are Green then the system appears to be booting but the monitor display is not functional

You probably removed the "primary" CPU,
and the computer cannot operate only with the "secondary" CPU installed.

Move the CPU from the "secondary" slot to the "primary" slot.

Here are some things to check

1. Power LED (It should be solid green) if flashing or solid Amber, then a power supply or motherboard problem.
2. On the back, near the PS2 Ports, are 4 diagnostic LEDs marked ABCD. When running normally they are all green. During boot they flash on and off during each sequence of the POST, if they stop at t code AAGG for example is bad RAM
3. If the Power and Diag LEDs are normal, then reseat the video card if an AGP card is installed or remove it an try the integrated video.

AAGG is an indication of a memory error, reseat memory modules, if no luck replace the RAM

Usually when it sits like that it is checking for problems. Some Dell computers have indicator lights on the back of them labeled ABCD, your model might be one of them, look at those lights and see if there is any orange ones. They should all be green but if there is a solid orange it has detected a problem. You should also open it up and make sure all of your components are set in their place nice and tight and it isn't covered in dust.