IP35 won't post after power is disconnected.

[oSkar]

Hi, I hope someone can help me.

TL,DR: Whenever I disconnect the power from my PC, it looks like I need to clear the CMOS before it will POST. I've updated to BIOS 14 and now it may not POST at all.

I recently received an Abit IP35 as well as some other parts for a new PC I am setting up.

Here is my parts list:
Abit IP35
Intel Q6600 G0 Core 2 Quad
Tuniq Tower 120 CPU Cooler
4 x 1GB Corsair XMS2 PC2-6400 DDR2 CAS4 memory (2.1 volts)*
BFG GeForce 8800 GTS 320MB OC*
Creative X-Fi Xtreme Music*
Enermax Infinity 650W PSU
2 x 74 GB Western Digital Raptor HD*
2 x 500 GB Western Digital HD
Pioneer DVD-RW
Antec P182 Case

* These components aren't new, I've had them for about a year and they've been working fine.

I also have a pair of 1 GB Corsair ValueSelect PC2 5300 DIMMs that I was intending to use in another system. I have also used these DIMMs in the PC above and they worked.

When I first built the system everything was fine. Initially I had the system working with the XMS2 ram at 1.8 volts. I tried changing the BIOS settings to 2.1 volts but the system wouldn't POST after I changed this setting so I cleared the CMOS and everything was fine again. The system worked well enough to allow me to install Windows Vista and run a few stability tests like 5 minutes of Orthos. I don't know if it could run for longer than that, I wasn't overclocking anything so 5 minutes was enough for me to think everything was stable. I was having some problems in Vista where the system would BSOD if I ran the Vista experience benchmark. It would also BSOD if I started up Media Center. I tried the usual stuff like updating to the latest nVidia driver but it didn't help. I thought there might be some issue with my RAM running below the proper voltage and I found that version 14 of the IP35 BIOS was supposed to fix the issue with setting DDR2 voltage over 2.1 volts. I shutdown my PC, disconnected it from the power for the first time and hooked up a floppy drive from another PC and installed the ValueSelect memory, just to make sure that the possibly dodgy, under-volted XMS2 memory didn't mess up my BIOS update.

I powered up the PC, and it wouldn't POST. I just got a blank screen. I had not updated the BIOS at this point, only connected the floppy drive. I needed the computer to boot into Windows so that I could put the BIOS update on a floppy. At this point, I tried reseating and reconnecting everything except the CPU. Nothing worked, so I decided to go watch some TV and come back to the PC after an hour or so.

This time, it booted up with the XMS2 memory installed after I cleared the CMOS. I figured the ValueSelect stuff was dodgy so I tried to confirm it. I disconnected the power, swapped the memory, and the system wouldn't POST again. I swapped back to the XMS2 memory, again disconnecting the power, and the system still wouldn't POST.

Now I was worried I had either a toasted set of memory or a toasted video card. I tried the video card and one stick at a time of each of the 6 DIMMs I have in my one year old Gigabyte GA965PDS4 and everything worked fine.

I went back to the IP35 manual, found the procedure for the full CMOS clear which includes disconnecting the PSU from the motherboard and taking out the battery, followed this procedure and managed to get the IP35 to post and boot up into Windows using the ValueSelect memory. By now I had figured out that the problem may be something to do with disconnecting power from the PC so I did all the work with my PC up on a bench and without disconnecting the power or switching off the PSU. I made up a floppy with AWDFLASH and IP35 BIOS 14 and tested copying the files off it a few times to confirm that the floppy wasn't corrupted. Then, I updated the BIOS on the motherboard to version 14. The BIOS update worked successfully and as soon as the PC posted after the BIOS update I went into the BIOS setup, loaded the optimized defaults and then saved and rebooted the PC. Everything worked fine as I swapped in a stick of the XMS2 RAM, set the BIOS up for my RAID config and increased the memory voltage to 2.1 volts. Windows booted fine with one stick of XMS2 so I shutdown the PC, installed the other 3 sticks and booted up windows again. The Abit eq utility told me that my voltages were applied fine with 2.08 volts on the DIMMs and no unusual system temps. I noticed my CPU temp was 10 degrees C higher with BIOS 14, but nothing too unusual, before it was 30C and now it was 40C at idle. The system could run 5 minutes of Orthos without any errors. I also noticed that the system no longer double-booted after a full shutdown.

I decided it looked like it was as good as it is going to get and I was hoping that BIOS 14 had fixed the issue. I shutdown the PC, disconnected the floppy drive and reinstalled my X-Fi, which had been left out so I could get easy access to the Clear CMOS jumper. I booted the PC up into Windows one more time to confirm everything was working with all the components installed. It worked fine and I ran another 5 minutes of Orthos just to make sure. Then I shut the PC down and disconnected the power so that it I could move the PC off the bench and onto the floor. I hooked everything up on the floor and powered up the PC, but it wouldn't POST. I tried clearing the CMOS along with disconnecting the PSU and removing the battery, but it still didn't POST.

At this point, I decided to go write this forum post to see if anyone could help me with some ideas.

Could a short from the case to the motherboard cause something like this?

Is it worth building the PC outside the case to see if I get the same problem?

Should I just contact Scan and get an RMA on this board and hope that the next one works better?

Any suggestions would be appreciated.

[oSkar]

Update:

I've gotten the IP35 to post now. I had been trying to POST after a CMOS clear with all 4 DDR2 slots filled with the XMS2 memory and I guess that was too much for it. I swapped in the ValueSelect memory and got it to post. Then I swapped in 1 stick of XMS2, set the appropriate settings in the BIOS and now I'm up and running in Windows with all 4 sticks of XMS2 installed.

As far as I know, my problem is now just the situation where the PC needs a CMOS clear before it will POST after an AC power interruption. It makes it kind of inconvenient if I go to a LAN and have to do some PC re-assembly before my system will POST.

[oSkar]

Another Update:

It looks like my problem is a dodgy PSU. I tried running the system with a different PSU (An Enermax Galaxy) with the motherboard sitting on a cardboard box and everything worked fine. I connected the Infiniti again and the problem came back. Looks like I need to RMA the PSU.

I bought the PSU from Scan so I'm hoping they can help me out.