I'm having the same problem as this guy...

http://www.tomshardware.com/forum/252581-31-bios-post

My system stats...

MEMORY (4 sticks): G.SKILL 2GB 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400)
http://www.newegg.com/Product/Prod [...] 6820231121

VIDEO: HIS Hightech H700H64-1TOPN Radeon 7000 64MB
http://www.newegg.com/Product/Prod [...] 6814161011

MOTHERBOARD: DFI BloodIron P35-T2RL LGA 775 Intel P35 ATX Intel Motherboard
http://www.newegg.com/Product/Prod [...] 6813136038

The bottom line is everything works with 4GB of ram but with 6GB or 8GB it freezes on post. Heres what I sent to DFI tech support...

"Everything is fine when I boot with a single 2GB stick of ram OR two 2GB sticks
of ram. No matter what slots there in or there order, I can boot with a total of
4GB of ram with 2 sticks. BUT when I add a third stick of 2GB of ram, I
can't fully post. It only gets as far as displaying what cpu I have and the
prompt at the bottom to hit delete to config the bios. But theres no response
from the keyboard to hit delete to configure the bios. The exact same thing
happens when I add another stick of ram for a total of 8GBs of ram. I did some
googling and found other people had this same problem but with different mother
boards and they suggested to change the drams voltage on the motherboard to what
the manufacture of the memory chip suggests. I did and no such luck. But the
bottom line is from what I've seen it looks like the motherboard can support
4GBs of ram without any configuration in the bios but anything over
that
requires a bios change but I just don't know what. I also tested each stick
of ram in other computers so I know all 4 2GB sticks work.
"

Heres what they sent me...

"
I had got the symptom when insert 4 piece GSKILL 2GBPQ memory.
That will be work fine when I seting BIOS "DRAM Voltage Control" to 2.10V.
Please see attached capture the system run Sp2004 X2 by BI P35 BIOS 2008/5/2 with 4 piece GSKILL F2-6400CL5S-2GBPQ memory.
"
It didn't work and this is what they sent me as well...

"
Please follow this instructions from our Taiwan support team:

1) Update BIOS to the 5/2/2008 version on our website by copy and paste the
link on the previous mail. You can obtain the same model name by testing with
CPUZ.
2) The 'DRAM frequency' detected by CPUZ is 400MHz. Since it is DDR2,
the Data transfer frequency is twice of DRAM frequency and it should be 800MHz.
3) To fix the problem of installing 8GB of GSKILL memory on the mother board,
please put the
first 2 sticks into the white color slots (DIMM1, 3) and then
change the setting of the BIOS to:
DRAM Voltage Control------ 2.1V~2.275V
NB Core Voltage-----1.33V~1.45V
4) Hit F10 and save
5) Insert the rest of the 2 sticks."

I did all of that (especially the bios update) and still no such luck. This was my response...

"I tried it and it didn't work. I took out the network interface card so I had just a bare system using only the bare components needed to boot. The ONLY other thing I have connected in that motherboard besides the 4 sticks of memory is a video card...

HIS Hightech H700H64-1TOPN Radeon 7000 64MB 64-bit DDR PCI Video Card

To make sure the problem wasn't something else I configured in the bios, I reset the bios to the "failsafe" config and changed the DRAM voltage to 2.10V and got the same failure. I then reset the bios to the "optimized" config settings, changed the DRAM voltage to 2.10V and got the same failure. To make sure it still wasn't the ram, I tried each memory chip in other servers I have and they work flawlessly. To make sure I could still use 4GB of ram, I took out 2 sticks as was able to boot off of the remaining 2 sticks. I switched those 2 sticks with the ones I took out and booted just fine off of those memory sticks to make sure no matter what combination of memory sticks, I'm always able to boot off of 4GB of ram.

I was looking at the specs from the screenshot you sent and it looks like the motherboard your using is different from the one I'm using. Your screenshot said...

INF P35-R

But my model number is...

INF. BloodIron_P35-T2RL
"

I tried changing my timing to 5-5-5-15, I lowered my DDR Mhz to 533. I'm at my total whits end. All 4 sticks of ram work FINE when there are 2 or 1 of them in the system. And they work on other boxes I have as well but just not in this one. I think theres nothing wrong with the motherboard since everything is fine with 4gb. I even installed windows xp without any problems. It's GOT to be a config issue in the bios but theres a zillion things to configure and with the little amount of debugging info I get on the screen, it's anyones guess as to whats wrong.

Check each memory stick separately in CPU-Z and confirm that both the SPD and memory tabs are identical?

If you have the ability, I find pictures of your BIOS settings and screenshots of CPU-Z can help and get you more replies

I'm getting a digital cam tomorrow for that exact same reason but how can cpu-z work on my box if I can't even post?

No, test the individual sticks, one at a time. Install the OS with 2 or 4 GB, then run CPU-Z with just one stick installed. Do that 4 times so that you get readings for each stick separately. If the voltage requirements or timing is not really the same for all 4 sticks, you have your problem.

Another possibility would be that your PSU can't deal with the extra sticks. Sure, we're not talking about a lot of wattage here, but sometimes the voltage regulation goes bad at a certain load. This of course would be far more likely with a no-name PSU or a very cheap one.

I slapped on windows, booted to 1 stick of ram at a time and ran cpuz. Here are the screenshots

http://65.39.81.52/newbox/stick1-sum.JPG
http://65.39.81.52/newbox/stick1-details.JPG
http://65.39.81.52/newbox/stick2-sum.JPG
http://65.39.81.52/newbox/stick2-details.JPG
http://65.39.81.52/newbox/stick3-sum.JPG
http://65.39.81.52/newbox/stick3-details.JPG
http://65.39.81.52/newbox/stick4-sum.JPG
http://65.39.81.52/newbox/stick1-details.JPG
http://65.39.81.52/newbox/sum1.JPG
http://65.39.81.52/newbox/sum2.JPG
http://65.39.81.52/newbox/sum3.JPG

almost forgot, heres the power supply I'm using...

http://www.newegg.com/Product/Prod [...] 6811129024

If you edit that post and put img tags around those links it will help some...

They seem to be all the same, but I do see some interesting items:

Your CPU is running at 266 x 6... for a total of 1.6 Ghz... this is probably just throttled down for an idle state, but make sure the actual multiplier is 9.

Your memory is not running at the settings provided in the SPD for 266 FSB. See if it runs at those timings, all of them.

Given the 1.8V base, it seems a bit extreme to me to recommend up to 2.275V to get 4 sticks running.

Are you running a 32-bit OS or a 64-bit OS? If you're running a 32-bit OS such as XP, that could be you're problem since a 32-bit OS maxes out at around 3.5GB's.

"Your memory is not running at the settings provided in the SPD for 266 FSB. See if it runs at those timings, all of them. "
What does that mean? SPD? There ddr2 800's so technically, wouldn't they run at 400Mhz?

"Given the 1.8V base, it seems a bit extreme to me to recommend up to 2.275V to get 4 sticks running."
Does the voltage requirement mean I have to have 1.8V per stick or total to make all 4 sticks run?

Runswindows95: I'm using 64bit ubuntu but it doesn't matter since it can't boot into the hard drive when I have 6GB+ of ram

Your SPD tab shows information provided about possible settings for your memory. It is not a statement of what the settings ARE, but what they SHOULD BE.

Your FSB is set to 266. Your RAM should be set there too. Here are the settings you should put in your BIOS, under the 266 column:




The 1.8V is the power needed for each stick, yes, but it's not additive. In a perfect world, your motherboard would supply 1.8V to each slot with no issues... but failing that it might need a little boost to make it there. 2.275V just seems like way too much to me, and I'm surprised a tech would tell you to go that high. 2.0 maybe.

I'm making the bios changes now and I configured everything except for 2 things because I don't know where they are.

Would the tRC be named something different in the bios. All the other timer settings names in my bios match the names in the screen shot but I can't find the tRC, would it be called something else?

As for changing my frequency, these are the only options I found with 266 in the name..

266/667
266/800
266/1066

p.s. Why wouldn't I want to use the 400 Mhz column, wouldn't that make the memory faster?