Need help, PC does not start

[Kam]

I recently installed a ATI X1900XT 512mb Graphics card and the PC does not start, only the fans start spinning. Sometimes when It does start, it shuts down shortly after woods. I checked the CPU temp in bios previously and the temperature was around 80-85c. I am thinking it could be the MB, CPU or PSU. Previously, the MB would not start unless i put washers on the screws, now even with washers it does not start. Can someone pls help.

Specs:

Antec Sonata II case, 450Watts
Gigabyte GA-81955X Royal MB
Intel Pentium D 920 2.8Ghz, L2 Cache
Corsair Memory TWIN2X1024A - 4300C3PRO XMS2
HIS ATI Radeon X1900 XT, 512MB GDDR3 (requires at least 450Watts)
Hitachi Deskstar 160GB SATA2
Pioneer DVR110
Sony F.D

 

[Rik]

The cpu should not get that hot that quickly!!!! Did you fit the heatsink and fan correctly????

 

[Tedster]

Can your PSU handle the new card? Did you use proper thermal grease with the CPU? Check out the NO POST guide in the guides forum.

 

[Rage_3K_Moiz]

It's definitely ur PSU. That card and CPU are very power hungry so 450W is very low. Get at least a 550W or greater PSU and the system should work fine.

 

[Kam]

I checked the cpu and heatsink installation and it looks fine, I even re-applied some Arctic Silver 5 thermal compound. Could it be possible that the MB would need replacing.

I bought the MB about 6 months ago and it comes with a circuit called U-Plus DPS (Universal Plus Dual Power system) which is a eight phase power circuit and fitts into a slot close to the cpu. According to the manual, the U-Plus DPS should provide a stable power circuit to the cpu. I am thinking maybe this U-Plus DPS also requires more power and it's not working becouse of other power hungry components which leads to the PSU requiring more than 450 Watts. Or it could be the MB which has a faulty component i.e. the U-Plus DPS.

 

[Rage_3K_Moiz]

I am 100% sure the PSU is at fault, because 450W is too low for a powerful system like that. The Pentium D in particular is well-known for being a real power-hog. The same goes for the X1900 as well.

 

[twite]

Its not the psu, if the cpu temp is 85 degrees then thats obiviously the problem, its the emergency shutoff. If its a socket 775, then its the heatsink thats the problem. They dont tighten enough, and don't make firm contact with the cpu. I had the same probem and rma'd my mobo thinking it was the temp sensor, but i got a a new one and had the same problem. Manually press the heatsink onto the cpu as hard as you can, or have a freind do it while they check the bios temp. I ended up buying a zalman hsf, and my temp went from 92 celcius to 35

 

[Rage_3K_Moiz]

Hmm, seems I missed that detail in the first post. Pentium Ds generally run hot but 85C is way beyond threshold temperatures. The case probably needs more fans.

 

[Kam]

At first I thought it was due to the Intel heatsink not pushed down enough, so I re-applied some Arctic Silver 5 heat paste and pushed that heatsink down and tightend it as much as I could (within reason, otherwise i'd break the motherboard) and still the system won't start. I then used some new steel washers to put between the screw and MB as I had a similar problem when I first bought the MB and had to use washers in order to make the PC boot. I also contacted Gigabyte previously and they also said to use washers. After using the washers on all the screws in this case, the system still doesn't start up and the lights on the U-Plus DPS won't light up which corresponds with the CPU and I am still unsure if it's the MB, CPU or PSU.

 

[dropzone2006]

might be a grounding issue
try those little gasket thingies the are used to prevent shorts in mounting the mobo and also reset the bios should clear any internal clock settings that may help it post

 

[Rage_3K_Moiz]

Washers and gaskets are the same innit?