My computer will not boot cold. When i first turn it on it will freeze at various point. 1st it wont even finish posting so I hit reset. Then it typically will get as far as the the black screen before the windows logo before freezing, so I hit reset again. 3rd time it usually gets to the windows logo before freezing so hit reset again. Then it might think about booting properly.

Here is my set up:
Intel Core 2 Duo 6300 @ 2.8 1.3vcore Heat sink: Gigabyte G-Power Pro
ASUS P5N-E Sli (bios 401) Nvidia 650i SLI chipset
2x512 Corsair XMS2 DDR2-800 5-5-5-15 T2 1.9v
2x1024 Corsair XMS2 DDR2-800 5-5-5-15 T2 1.9 (Rated at 5-5-5-12)
Sapphire Radeon X1950XT 256mb stock clocks
WD 200GB PATA HD 8mb cache
Maxtor 200GB SATA 3.0Gb NCQ 16mb cache HD
Lite On DVDburner
Lite ON DVDrom
Audigy Platinum
Dlink wifi G card

Power Supply: Brand spank'n new Antec TruePower Trio 650W All power rails are absolutly rock stable.
Here is what I have Checked:
1. The problem is the same at stock clocks and voltages.
2. It's not the RAM. I've ran it over night on memtest. The problem is the same with several different sticks and in single channel mode. The problem also occured before i put the extra 2Gigs in.
3. Originally this set up was powered by an Antec SmartPower 450. Becuase of the cold boot issues i assumed it was a PSU problem so I replaced it with the 650. This fixed the problem for about a week.
4. It still wont boot cold with all the pci cards and disk drives removed.
5. On a lark i removed XP and installed linux. Didnt help.
6. I reseated all the heat sinks, no improvement.


The crowner of this little jewel is that the computer is stable.
I can run Orthos for 72 hours straight with no errors.
I get no BSOD although i get random resets a couple times a week.

What gives?
Any help you can offer would be greatly appreciated.

Excellent job on the troubleshooting before posting!
You are a shining example for many others to follow in the future.

It could be the HDD, I don't see mention of you testing it. We usually assume that even though something is brand new, it couldn't possibly be the culprit. However, there is only one way to know for sure.

that does sound like the only thing left. i had problems like that when my hdd got corrupted for some reason... i would have to keep on restarting the comp and hopefully it would load up. so i had to completely erase my hdd and no problems since.

as for it being hard drive, two of my computers hang right after post before actually getting to the windows boot screen...its most likely the bootsector of the hard drive, the cable, or the hard drive on its way out. the computer may not be reading the boot sector far enough to make it all the way, have you tried replacing the ribbon cable on the PATA drive? that would be what i see as causing the problem, also, don't leave external drives plugged in and switched off [if they have a switch] as that can cause a problem with a long boot time.

I have replaced the hard drive cables several times and the problem still remained.....
One more thing ... it even freezes inside BIOS! I dont know what the bloody hell is going on.
There are no external drives connected to the computer.
The problem persistes even when booting from LiveCD into linux.

My only remaining ideas are that it is the GPU, the motherboard, or a bloody ghost that i must excise with holy water!

It's either the motherboard or the PSU.
Try doing a barebones setup (mobo, CPU, RAM, HDD, video card and PSU) outside the case and on a flat surface with anti-static wrap (or wood). Use a flathead screwdriver to touch the two pins used to power the system and see what happens. It could a stand-off issue where it's not seated properly. If a stand-off is touching the board it could be causing it to freeze like you're describing. I see you did this for your heatsinks, but try the mobo.

I got a brand new P5N32-E SLI board and had a similar problem. The only difference is that it would boot up cold w/o a problem, but not POST on a soft reset. I posted on the ASUS forums and got all sorts of complicated speculations on the problem. However, I failed to do one of the most basic things when troubleshooting a PC... try the easiest fix first.

My mobo had the 0602 BIOS on it. It is a year old version. The latest version 1002 came out 3/30/07. I used the phoenix flash utility with a windows98 boot disk, and flashed the BIOS (the ez flash utility within the BIOS would freeze before I could even specify the .bin file). After one power cycle, the problem went away.

There is a new bios for your board, the P5N-E SLI (version 0505). Here's the description:



The release date for this bios is 3/16/07. I strongly suggest you upgrade it. Make a 98 boot disk. Copy the bios flash util (http://dlsvr03.asus.com/pub/ASUS/mb/flash/AWDFLASH119.zip) along with the bin (http://dlsvr03.asus.com/pub/ASUS/mb/socket775/P5N-E%20SLI/0505.zip). And flash it the old fashioned way.

After I restarted my computer, the problem persisted. However, after I powered the system off, then turned it back on, it was gone forever (knock on wood). No CMOS resetting. No chip reseating. No voltmeters. It's worth a shot.

Godspeed.

An outdated BIOS... I didn't even think of that. Interesting. *Adds to list of things to check when advising other people*

Thank you for the update on that, betamax.

Neither did I. I paniced initially. Only after smoking a joint with my roommate was I able to mellow out and think of checking the BIOS.

Did it work for you??