motherboard / PSU problem

[am21]

I assembled a system with Gigabyte GA-K8N51GMF-9 mobo with athlon64 3500+ 1gb ram and 250gb hard disk etc

the problem i faced is failure to POST if kept turned off for few hours (OFF from main power outlet) since i had a warranty i asked my PC assembler to figure out the problem.

they simply told me that it was a bad PSU and replaced it. this happened 3 times (replaced 3 PSUs)

actually the same PSU works fine in other systems and it will work in my system if kept ON continuously. i think it is a serious problem with Gigabyte motherboards.

i did a small research and found these links :

http://forums.pcper.com/showthread.php?p=3663475#post3663475
http://www.hardforum.com/showpost.php?p=1028898900&postcount=265
http://forums.pcper.com/showpost.php?p=3672473&postcount=7

2 days later.. i asked my PC builder to replace my mobo

my new mobo model : GA-K8NF9 Ultra(Rev 2.x) nforce4 ultra/SLI
now i'm experiencing the same boot up problem. i'm currently typing this from my laptop.

Please advice me regarding this matter.

more info about my motherboards (comparison)
http://www.gigabyte.com.tw/Products/Motherboard/Products_ComparisonSheet.aspx?ProductID=1939,2268

 

[CmdPT]

Have you tried using 1 stick of RAM. It might be that. Since you have 1 GB RAM then u should have 2 x 512 MB ram but if its only 1 stick of 1 GB ram then your out of luck but try that first see what happens.

 

[Jizumonkey]

Any problem I've ever seen to do with a system not posting when the power has been turned off at the mains is to do with the CMOS battery.

I'd perhaps not take their word for it that the mobo was replaced and try another battery or simply confirm the voltage of the current one.