**Official DFI LanParty UT 790FX-M2R Review/Overclock/Guide Thread**

[Oliverda]

Has anyone tried the 800MHz memory mode around 250MHz FSB? It always stucks on post code 25.

(1/30/2008 BIOS with Phenom 9500)

[serial099]

Unplug the P.S.U use only one stick of Ram closest to the CPU , Clear Cmos for 10 minutes , plug back in the P.S.U wait exactly 40 seconds , Use a PS2 Keyboard as its booting up hold down the Insert, and Home Keys for about 6-7 seconds release and it should boot!

Do you think this same advice may work for my situation? I am able to boot, but only with ram slots one or two occupied (three and four unoccupied). Is this something that is fixable or am I going to have to RMA the board?

[Rammsteiner]

[/B]


Why would you do that? You know you are just asking for problems when you change Motherboards and are too lazy to do a fresh install

Wasnt really lazy to re-install, I was more like too lazy to call MS for a new code as I was changing mobo's. But in Windows Safe Mode it worked after all.

@ Oliverda

Well, I always get '25' when ever I get a BSOD which is very most likely RAM related. I simply get rid of it by pulling the power plug, wait for the LEDs to go out and put it back in. If it doesnt work CMOS reset.

If that doesnt work it's most likely you selected too tied timings and/or too high Mhz for the RAM and thus cant stay stable to even get into BIOS, so you'll have to reset CMOS then.

But it's possible, Im running 14x251 and DDR800 fine.

[EDIT] However, now I see you're using a Phenom. Ive no idea whether you forgot a 'Phenom' option in BIOS?

[Iketh]

sorry if this is already common-sense with all boards that are run outside a case, but it's caused me a few headaches since i got this board in december

my cell phone locks up my system every time it does a synch if it's sitting anywhere within 5 feet of the board...

90% of the lock-ups i've had previously was because i placed my phone near my board... all those mysterious lock-ups 5-30 minutes after finishing a successful prime test were from my moto razer

[3oh6]

well gents, i decided to give this board another go and the new one showed up today with a beautiful C1 for the Phenoms. with the 3200+, however, i am up and clocking like it should. that first board being stuck at 133MHz HTT was just a borked board.

it came out of the box on the 11/22 BIOS so i am going to leave it on that for now with the 3200+ while i get to know the board then i will tackle the Phenoms on it. just wanted to say thanks again for the help the other day and i am sure i will be posting results/asking questions soon enough.

[Iketh]

updated sig... been running this o/c with a much lower cpu voltage

[llenkoll]

Unplug the P.S.U use only one stick of Ram closest to the CPU , Clear Cmos for 10 minutes , plug back in the P.S.U wait exactly 40 seconds , Use a PS2 Keyboard as its booting up hold down the Insert, and Home Keys for about 6-7 seconds release and it should boot!

sent the chip in already, but im gonna keep this for later use, thanx.

[Jaivan]

Has anyone tried the 800MHz memory mode around 250MHz FSB? It always stucks on post code 25.

(1/30/2008 BIOS with Phenom 9500)

I'm running at 255MHz FSB and 800MHz memory.
Have you tried to lower the NB multiplier i'm using x8 instead of the stock x9.

[Rammsteiner]

I'm running at 255MHz FSB and 800MHz memory.
Have you tried to lower the NB multiplier i'm using x8 instead of the stock x9.

Bah, I want +5x NB multie's too.

Anyway, I heard in order to reach higher RAM OC's it 'might' help to increase Vcore over 1.52~1.53V? Is that true? I could test it myself but it's finally running nice now and dont want to go trough the hell of 'forgetting to reset Memset and thus freezing' etc. Just wondering if someone knew more about it?

[Jaivan]

I'm having a strange problem when i go to shut down my computer it goes through its normal process but when it turns off it automatically start up again is there a bios function that i need to turn off or something to stop this from happening?

[Brother Esau]

I'm having a strange problem when i go to shut down my computer it goes through its normal process but when it turns off it automatically start up again is there a bios function that i need to turn off or something to stop this from happening?

I doubt this is the case but....on the DFI NF4 Boards it would do that if wake from Lan was enabled in the NIC (advanced) tab try that and see if it works but as I said I don't think thats the case here.

[MKroenke]

Does anyone know which RAM slots should be prefered? btw: 1T timing seems to work only with the DDR2-667 divider, right?

[Sejo5]

Hey, Guys been checking out this thread due to the mysterious speedfan killing spree. Its been brought to my attention that the program has killed my cousin's (||ENKO||) board.

I have never heard such a issue, and personally i cant see it happening. If the issue did occur by speedfan accessing the bios to check the temps on the CPU and mobo its possibly a BIOS issue. Cause if any program that has to access the bios for info happens to corrupt it can cause a potential danger, such as CPu-z, Sandra, etc.


One of the DFI tech's has recommended that its the BIOS chip. Which i doubt unless speedfan somehow corrupted the BIOS. Has anyone have had this issue and went with the steps such as clearing CMOS, pulling PSU connections, Changing order of Ram or new Ram, and most important reseating the CPU -


Reseating the cpu i have found has done wonders when boards mysteriously wont post. Due to the voltage it can hold until the unwanted volatage properly expells. Usually holding the power button will remove unwanted power through out the board but hey sometimes it doesnt work.. So go alittle deeper and reseat the CPU and test the board outside the case and go from there. and check for silly grounding connections in the case.


Grounding can cause erratic behaviors and sometimes its the last thing people can pinpoint.
IF someone has already dones this let me know the outcome or have found a different technique that provided vauluable outcomes.

Thanks
Sejo

[serial099]

@Sejo5

I am one of those mysterious speedfan people. I swapped out the bios chip on my board with my wife's computer (both have this board in there) and the C1 fault isn't present on her computer with my bios chip. It boots up just fine. When I talked to DFI support they told me it had to be RMA'd to get it fixed. I suppose it possible it could be a CPU reseating thing, but somehow that just doesn't make too much sense to me.

[Sejo5]

Hey, I proposed the CPU reseating as a solution not a direct effect from what speedfan must have done. And why did you have to RMA the board if your wife has the same board? you could have done a Hot swap theres actually tutorials on how to do so. A good way to save money and time.

Hot Swap.

Two Identical boards. 1 Dead 1 working.

Removing the Bios Chip which is a 8MB from the non working mobo, having it ready in hand.

Turn on working mobo, boot to dos. (Dos does not access Bios in this point in time so you can remove the chip while it actually still on) make sure you have a Bios Flashing Utility. That runs through dos and a bios that you would like to flash diff manufactures have dos flash utilities. Some dont.
Once you have it in dos. Remove the Chip from working board and put in old chip. Removing chip can be done with paper clip, check tutorials if still not confident. Once old chip is put in, run flash utility and flash the chip with desired bios. when complete shut down PC and turn on again too see if it works. Which it should. Voila now you can put the one you just removed into the dead board since theres no point to remove the one you just flashed there the same chip same bios. So there you go. Corrupted Bios Revived.

Hopefully it was clear and understanable any questions just ask..

Sejo!

[Sejo5]

I just read yours again, sorry didnt understood that you actually put your old chip into her mobo and it worked. Thats actually weird. But have you re-seated the CPU and remove the mobo out of the system ? Try that and see if anything changes...

[Rammsteiner]

http://www.xtremesystems.org/forums/...&postcount=183

Interesting, I asked this earlier but no one didnt answer and I lost where I read it but I found it again. Should check it out actually whether this will let me run 292Mhz on the RAM, if it will Im so happy.

Does anyone know which RAM slots should be prefered? btw: 1T timing seems to work only with the DDR2-667 divider, right?

Is this true? And do you mean if the RAM effectively runs at 333Mhz or if you use the 667 divider and run it any speed?

[MKroenke]

http://www.xtremesystems.org/forums/...&postcount=183

Interesting, I asked this earlier but no one didnt answer and I lost where I read it but I found it again. Should check it out actually whether this will let me run 292Mhz on the RAM, if it will Im so happy.


Is this true? And do you mean if the RAM effectively runs at 333Mhz or if you use the 667 divider and run it any speed?

When I use AUTO, the Board runs 1T with 800MHz divider. But if you set the 800MHz divider manually it will only do 2T no matter which settings you use in the MCT Timings menu.

[Rammsteiner]

When I use AUTO, the Board runs 1T with 800MHz divider. But if you set the 800MHz divider manually it will only do 2T no matter which settings you use in the MCT Timings menu.

K, that's it. Ive seen a lot of new options on the net now to maybe improve things. Gonna check it out then

[BadNizze]

When I use AUTO, the Board runs 1T with 800MHz divider. But if you set the 800MHz divider manually it will only do 2T no matter which settings you use in the MCT Timings menu.

Same for me! 1T does not work if you sett it manualy... Other then that the new bios is great! No more 600mhz bug Priming my VX2 @ 600mhz 5-5-4-12 @ 2,25v seams stable

[hubcap]

Hi everybody,
Brother Esau and friends, my friend bought the DFI UT 790-M2R under my advice because it seems like an awesome board. Also bought a 6400+ Black Edition to drop in it because I saw that was what you were running. It has been a nightmare. We RMA'd the PCU because it was the greatest common of the problems. Before that I tore my machine down to try CPU and memory in his. My CPU (3800+ Windsor) ran fine with each memory installed. His memory is Patriot PC9200 2gb kit (2 X 1GB, I think the PN is PDC22G9200ELK (not sure of PN as he has gone to bed, will correct tomorrow if wrong). Could not finish XP set up with his CPU. Loaded XP fine with my CPU then changed back to his and would only get half way through booting and just shuts off. Also noticed temp of around 85C from cold to just BIOS, which I thought was a little high. The other thing is the memory is being recognized as 800MHZ. Board came with November's BIOS and has been updated after the trouble and RMA to 1-30-08. Any help or suggestions from anyone is more than welcome. I really dont want to buy him a CPU to replace the one I recommended.

[Rammsteiner]

Today I decided to look for another try to run the RAM at 293Mhz. I played with all variables. Though I didnt manage to reach my goal however Ive learned a lot about the Drive Strengths!

Stock are 1-1-1-1.5-1.5-1.5, after a lot of playing around I got 4x 1GB to run Super PI 32M 285 5-5-5-18 untweaked memory timings (as 285Mhz wasnt an option for me at all I didnt fine tune it).

I had to change the Drive Strengths to 0.75-1-1.5-1-1.25-1 to get the best results stability wise. Also increasing Vcore over 1.5V helps to stabilize the memory controller. Changing the CPU ODT didnt give me anything. DRAM Drive Weak Mode at Weak gave a lot of potential as well. Most likely due to running 4 DIMM's I couldnt hit my desired speed, but anyone running 2 DIMM's and trying to get a high OC really should look at the Drive Strengths! In my case lowering the Addr/CMD (aka Latency Drive Strength) had to be lowered a lot and MEMCLK (Pure Mhz Drive Strength) had to be higher.

It's really awesome, but I didnt feel like going 2.3V+ for the RAM as that wasn't worth it for me, but those Drive Strengths offer a very lot of potential!!!

[MKroenke]

Is it safe to tweak the drive strengths? Never had a DFI Board before this one, so I was never facing these options. But if those settings won't kill my RAM or Board, I'll try it.

[Rammsteiner]

Asked that a million times and never got a clear answer on that. It's known too high Drive Strengths can kill Micron chips quite fast in combination with high Volt etc. I just played with it to see what they do. But lowering them wont hurt the RAM I'd say, and using Weak mode will be only better.

[MKroenke]

I use the weak mode already but I never played around with the other options. Weak mode gave me around 20MHz at same voltage. Will try later with the lower drive strengths, maybe I could increase clocks even further without adding voltage.