GeckoLI

I recently built myself a new computer. Specs...

OCZ 4GB (2x2GB) PC2-6400C5 Dual Channel Vista Gold Series DDR2

Microsoft Windows Vista Home Basic 64-Bit

Gigabyte GA-P35-DS4 (Socket 775) PCI-Express DDR2 Motherboard

Intel Core 2 Duo E6750 "LGA775 Conroe" 2.66GHz

Asus GeForce EN8800 GT 512MB GDDR3 HDTV/Dual DVI (PCI-Express)

I am also using two 80 gig hard drives from my previous PC.

700w Power Supply



Ok basically this is what happens. I turn my PC on, it seems as if it is going to start and then... oh no. Off. The CPU fan does spin for about two rotations and then nothing and the whole things powers off. There seems to be little consistantcy to how long the powers srays on. Sometimes it's 1 second, other times the CD-ROM will spin etc and it wil go all the way to 10 seconds before powering off. It will continually power on and off in this manner if left alone.

It should be noted that sometimes if I poke around, unplug the power lead, reconnect and wait for a few reboots it does eventually boot up, the CPU fan will spin and I can use my computer confidently - as long as I don't turn it off.

Now this is what I've tried in varying combinations...

• Re-seating the CPU, reapplying thermal paste
  
• Changing the CPU fan with indentical fan
  
• Unplugging all non essentials
  
• Taking the mobo out and sitting the whole deal on a tea-towel to see if the mobo was shorting out on the case
  
• Using an 8pin instead of just a 4pin in the power connector next to the fan.
  
• Resetting CMOS
  
• Shouting at it loudly and other threatening behaviour

Any help would be much appriciated, thanks alot.

2pistolpacker

Hi GeckoLI, it sounds like a power issue to me, if you could post the name and model number of the power supply name and the +12v amp output listed on the side of the unit.
It seems the Gigabyte motherboards by default only provide 1.8v to the memory, the Vista Gold Series requires 2.1v and are warrentied up to 2.2v +/- 5%. Check in the bios to find the "DR2 Overvoltage Control"and see if you can raise it to 2.1v. Try this with only one stick installed.
Make sure you have the 24 pin, and the 8 pin power plugs connected to the motherboard and the 6 pin video card power connectors all firmly connected. Mike

GeckoLI

Thanks very much Mike, appriciate the help.

I can rarely get even to the BIOS stage but next time I am able I will try it and get back to you.

2pistolpacker

It really sounds like it isn't getting the minimum amount of power to start the computer, please list the info about the power supply. Mke

scapedriver

Gigabyte lists OCZ SLI "OCZ OCZ2N1066SR2GK" ram Volt rate 2.1 - 2.3

"OCZ2G8004GK" rate voltage 1.9, isn't listed ram with that model board. If the rig will post enough to enter bios try bumping ram voltage between 2.1 - 2.3V

GeckoLI

PSU is:

X-Power 700w (PCI-E. S-ATA, 24 pin, ATX12v v.2.2 compliant)

This one I think...

http://www.maplin.co.uk/Module.aspx?...=14&doy=search

2pistolpacker

Your PS has 4x 12v rails all putting out 16amps which is good, if the unit is working as is it supposed to. I would borrow one to swap in your computer or test yours in another computer. Try to get the ram voltage up first. Mike

GeckoLI

I only seem to be able to raise the voltage to 2.0 or 2.5. I'm trying 2.5. is this wise?

2pistolpacker

I'm looking at the manual for your board and it says the DDR voltage can be increased from 0.05 to 1.55v in 0.5v increments. Are you sure you have all power plugs in place, 1 - 24 pin, 1 - 8 pin and 1 - 4 pin molex for the PCI-e slot? Read page 55 of the manual for more info on memory voltages.

scapedriver

2.1V EVP** warrenty with ram installed thats not listed with Gigabyte for that board therefore 2.0 most bump I'd try.

more advanced BIOS Setup menu options, you can press <Ctrl> + <F1> in the main menu of the BIOS Setup program.

OCZ2N1066SR2GK listed for that board.

http://www.ocztechnology.com/product...n_dual_channel

http://america.giga-byte.com/FileLis...-p35-ds4_e.pdf

GeckoLI

Bumping the ram voltage didn't seem to work. There is no PCI-e molex slot that I can see, only an SLI one next to the 24 pin. The gfx card is connected to power using a 6-pin square thing.

This has me really stumped

2pistolpacker

This is Rev. 2.0,

Is this your motherboard?

scapedriver

Try testing 1 stick swapping them 1x1 for possible bad ram.

Gigabyte Memory Support List does not support that module number, the listed module number OCZ2N1066SR2GK is listed for that board.

imho swapping ram listed as supported by Gigabyte.

GeckoLI

Yes that is my mobo.

2pistolpacker

You need to swap in some different parts, another video card, and a different power supply to eliminate those as a possibility. Can you borrow any from a buddy? Have you bench tested the computer yet, completely stripped down? If not that is next. If so did it do the same thing as it is now? Here are the instructions. Mike Benchtest

scapedriver

Swap ram for Gigibyte's listed ram verified for their board, no need to rip your pc down.


http://www.gigabyte.com.tw/FileList/...ga-p35-ds4.pdf

GeckoLI

Ok guys, just discovered something that I think may be of significance.

When I unplug the 8-pin CPU connector so there is no longer any lead connected to it, the PC does not stall on startup as it has been and does not turn itself off (but obviously there is still no post or anything coming up on screen). This leads me to beleive that the problem lies with the CPU maybe? I know it can't be completely busted because sometimes my PC does boot up and it acts normal...

What could be going on?

2pistolpacker

Try another power supply. Mike

GeckoLI

Bearing in mind my system specs, how powerful of a power supply should I use?

2pistolpacker

I would try to borrow one before buying a new one if possible. Find a store with a good return policy if it turns out to be something else.
This unit is one we recommend, but not the only one.

Antec True Power Trio