runmc 9800 vcore mod

[vertices]

Well this sux.

I just toasted the memory on my 9800pro. I get green lines on the screen now even at post.

I've had the Vgpu mod done for a long time and was happy with the card. I just added ramsinks and the Vddr mod and increased my Vddr to ONLY 3.1 volts.

It gave me another 15 mhz on the mem. It worked for about 15 minutes and I was running Nature 100% artifact free and all of a sudden artifacts and green lines popped out EVERYWHERE. I quickly snipped the wire for the Vddr mod and rebooted and to my horror I saw the vertical green lines at post knowing I just fragged my card.

Bottom line, be careful with the Vddr mod. My card toasted at 3.1 volts with ramsinks.

DAMNIT!! This sux.

[runmc]

Sorry to hear about your card. I know you feel horrible.

[muzz]

Sorry to hear that vertices,

Seems from my experience the mem is pretty sensitive ( I have a couple here toasted ).
Just got a 9800p to mod/pelt myself, I hope I dont run into that, as this bitty won't do much over 360mem artifact free stock.

[CarNabY]

Vertices,sorry for what it is happened you
The yours 9800 is still in guarantee?

It seems me weird that itself fault of the too voltage. 3.1v I is not a lot! I use the my 9800 to 3.8V!!!

[vertices]

Originally posted by CarNabY
Vertices,sorry for what it is happened you
The yours 9800 is still in guarantee?

It seems me weird that itself fault of the too voltage. 3.1v I is not a lot! I use the my 9800 to 3.8V!!!

I'm sure I have no warranty as I have epoxied ramsinks on the card. Plus the soldering. I have now way of getting a replacement short of buying a new one.

Maybe I will get a 5900Ultra this time just to buy something different. It sucks having to buy the same thing twice.


I also was very surprised that 3.1volts killed it. Especially when others like yourself have run up to 3.8volts. I got unlucky I guess.

[CATCH22ATPLAY]

Originally posted by runmc
stock (default) volts for the 9800 are -

core(gpu) = 1.7v

ddr(mem) = 2.9v

That may be true however. Data sheets indicate ddr for the R9800Pro should be VDD=2.8 and VDDQ=2.8 and Vref should be 1/2 of VDDQ. Default Vcore is kinda hard to say. I think ATI tried for 1.60 volts and if it doesn't pass Q/A then they increase it. I've had the 4 i own anywhere from 1.606 to 1.775 volts. BTW the 1.606 volt card O/Cs quite nicely even before mods.

The 256mb R9800 should be VDD=2.5, VDDQ=1.8 and Vref 1/2 of VDDQ aka 0.900 volts. Wierd thing is increasing the o/c on that ddr2 stuff doesn't increase score as much as it does on the normal ddr. Quite dissapointing actually. Since i don't see a seperate controller chip for Vref i'd bet money it's just using a resistor divider network from VDDQ to get 1/2 of VDDQ voltage. Easy enough to do and only takes 2 resistors to set Vref btw. There is no reason to look for a Vref mod because when you raise VDDQ Vref will raise accordingly because of that resistor divider network. It will track exactly too. Mobos usually use the same technique for ddr too btw. I don't believe raising voltage for VDD or VDDQ will help much. I think we need to increase current. With my somewhat expensive multimeter i can tell when power is being maxed out. I get ripple voltage. This tells me how high i can raise voltages for Vcore or VDD or VDDQ. Increasing past that ripple point is a waste of time. I've tested this on numerous cards. Why we get such different O/Cs. Worse offender so far is the DDR2 with VDD. It's possible to eliminate ripple but it's kinda hard to do unless you wanna change parts outright and actually add parts. Sometimes just swapping out an Inductor may do the trick. I was gonna build an power supply just for this. But i chickened out. I'd really hate to fry a $500.00 vid card. Especially since O/Cing the ddr2 doesn't help enough to justify the mod.

If i was an electronic engineer this sure would be easier to figure out. Frankly i'm suprised that will all the people around the world O/Cing vid cards we never really get input from an expert. I seem to do fairly good at this type of stuff. But maybe i'm just lucky cause i really don't know WTF i'm doing BUt someone just try to beat my 82f air cooling and core o/c of 530 please. Oh that same card i've ran at up to 580 with extreme cooling btw. Too bad i can't get the ddr to run above 414 Oh well it's all good and quite fun. Good luck dudes

[Matt McFaul]

it would appear at first that you are reporting your results of the 9800pro 128mb but then further down you get into the ddr2 discussion. Are you actually modding and testing a 9800pro 256ddr2 version? If so I need your input on the mods. For one my vcore doesnt seem to much matter over 1.8v and maxes out at 510mhz.....and this is with an mcw50t on a dedicated meanwell320 and h20 rig with 4- 120x35mm y.s. tech 122cfm monsters sandwhiching the raddy.
My mem without modding maxes at 405 before the onset of artifacts and I have 2 80mm sunons and 1x120mm panaflow cooling the ddr2.
I am unbelievably interested in any info you can supply me with.
thanks!

[CATCH22ATPLAY]

Yes you are quite correct. I was replying to Runmc's post of R9800 128mb vid cards voltages. Then i tried to reply to your questions about the 256mb r9800Pro2 vid card. Let me add to my previous comments, Especially to your core max limit. More than likely you hit your limit. It would require replacement of parts for you to achieve a higher o/c. Or way cooler temps. But even way cooler temps isn't gonna help all that much. Either your core doesn't like more current or volts or you can't supply enough current with the components on your vid card. There are few ways to raise current. Only problem is it isn't all that easy. Also sounds like your card is probably getting voltage ripple when you try to increase voltage above above 1.80 volts. I've owned quite a few R9700's and R9800,s and R9800 256mb models. Some get that voltage ripple at as low as 1.825 volts. I've actually done about 10 different volt mods to just 1 card trying to fix this. It helped, but not enough imo. I ended up replacing parts etc. I won't even bother trying to detail everything i did. I do every card i own just a bit different every time. My R9800Pro2 256mb card core runs at up to 2.025 volts with 82f air. Slight color coruption is all. I don't mean to suggest you try running it that high. My core stays very cool or i'd worry about it. I usually run at 1.95 with 82f air 24/7. But as far as i know i'm the only one that can do that on air. Is my custom modded PSU having that much of a difference? Hmm well for $325.00 maybe it is, i dunno. Have you checked your 5v and 12v and 3.3v on the card when it's at max o/c? I've had excellent PSU'd5v line drop to below 4.6 volts when measured at diodes on the r9800. In fact one of my 400 watt models dropped to 4.2 volts. But my modded PSU doesn't drop below 5.00 when i set it to 5.225v. I haven't done enough experimenting on my 256mb card. I'm still trying to get #1 R9800 3dmark03 score using my 128mb card. The 256mb one doesn't like to run above 550 core But if i ever decide to play with that card more. I believe i may have an idea to raise core a bit more. Hell i know i do. But since each card has it's own particular problems and each require a bit different mod i can't exactly tell you what will work. After having about 5 128mb models and 1 256mb model all i can say is only 1 128mb and 1 256mb card would o/c better/higher than both my R9700's. If it don't do say 450-470 core stock then don't expect to get great O/C results even if you use LN2. But having said that if and when i get #1 R9800 score i'll see what i can do about this 256mb R9800Pro2 card. I have an easy idea brewing in my head that might work er maybe

[runmc]

No one knows volt modding like Catch22

Nice to have your input, Catch..

I know whenever I need help with, or have questions about a v-mod, I always run to the master "Mr Catch"

[Matt McFaul]

thanks I look forward to hearing more when the time comes!

I have a modded enermax and an antec true control 550 on this sytem and have attinuated all settings to what will stabilize the rest of the system. I have tried running just the enermax on gpu but that didnt make much difference...my voltaes seem really stable...unussually actually cept for the vcore but thats a different story (problem coil caused by old noisey vantec 520 i think).
Im content for the moment since funds are heck alow so take your time...hehe!

thanks again

[CATCH22ATPLAY]

Thanks runmc Matt it sounds like power may not be a problem. But I've never owned an Antec or an Enermax that i liked. Maybe i was unlucky. But mine really sucked. 5v lines dropped way too way on mine. I haven't tried that true control though. I do have another PSU that i set to 5.3 volts and when i checked volts at the diode next to SC1175 chip the voltage was 4.50 Take a reading right there. It's that big mofo right next to the SC1175 chip. 5v one side and 3.3v the other side. BTW i always solder an extra 5v wire to the 5v side of that diode to a spare molex cable. I mean spare as in make sure it's not on the same molex as you already got plugged into the card. Take it from the hdd if you have to. That usually increases voltage 0.200 alone. I've tried a second PSU to see if that would help. But it made things worse. My other PSU's just can't compare to my pcpowercooling psu. 80amps on the 5v line n/p hehe i tested it.

OK now it's time to fry another mobo. Dryice time and here's for attempting P4@4.2G+ and R9800@580/414 or so. Hmm might even try 2.20 volts for gpu core again. But damn the screen looks fugly :smileysex

[bowman1964]

hey catch whats up my friend.long time no see.
i am doing a little reading and i see you post...

runmc glad to see this post,you did a fine job.

i may try out some of the mods,since i just got a r9800 and a 1700 that is suposed to do over 3.1g.so i might give them a run..

[CATCH22ATPLAY]

Hiya bowman1964 A 1700 that does over 3.1G? Damn i'm jealous. Very nice and i hope it does it. Was about to start my dryice bench but my computer turned off on me. Seems i left my a/c for my water cooling. I haven't insulated anything. So i just spent the last half hour + with a room heater drying up all the water/condensation. Arg i been trying to get that #1 R9800 score for almost a month now. Every time condensation kills me. Gonna attempt again after pizza. Hey good news though. I thought maybe i fried my 3.2G P4 a week ago or so. Well i just stuck it in this heated up/dried out rig and she's working again WOOHOO!!!!. I was sweating that one. Needed it for this run. Wish me luck

Oh hey you wanna know a secret? Don't biatch slap me for telling either people, you know who you are. Try lowering VDDQ on the 128mb R9800 to as low as 2.50 volts. Has helped a few people. Ain't done sheit for me though. Just test it and see. Use a 50k ohm variable resistor on both sides of R134. Not to ground. Basically you're just lowering the resistance of that fixed resistor. Hm i hope it's R134. I can't read it atm. It's the resistor closest to agp slot er well dimm slot actually. Also next to what looks like C140. Hope it helps someone.

[runmc]

Does someone have a pic of this v-core mod, using a grabber?(micro clip)

[Mac0r]

Originally posted by runmc
thank you
I used a dab of silicon(atx)

where could one purchase this?

[lostark374]

does any one have a pic of vcore and vmem with grabbers? id appreciate it greatly

[runmc]

Originally posted by Mac0r
where could one purchase this?

You can pick up silicon at any Auto Supply.

[krag]

Thanks runmc!! This thread inspired me to do the GPU v-mod! I did it and it works great!!!! Right now I have my 9800 Pro GPU voltage at 1.87 with a 500mhz core!!! My current card (Gigabyte) runs at 500/384. My 3DMark2003 score is 7,027!!! whhoohhoooooo!

Now I just need to do the v-mod on my mem.

BTW...I used a small patch of black velcro instead of silicone. Works killer!

[runmc]

good clocks!!!

velcro is a good idea, and so is double sided tape.

silicon works good, but the velcro and tape would be easier to clean up

[wkljohn]

you better use some alchole to clean your card

[SlimHitman]

Originally posted by lostark374
does any one have a pic of vcore and vmem with grabbers? id appreciate it greatly

Here is a link to the 9800p vmods with grabbers if thats what you guys were looking for.

Does anyone know if any old 20kohm multi-turn resistor will work?
The only 20k i can find is a square Vernitron brand and i don't know how many turns or watt it is.

[(F)rossen]

Would all of these fine mods work on my Excalibur r9800 non pro, wich should arive tomorrow?


Other info

It will be cooled with a dangerden and a blackice pro radiator, so there should not be a problem transfering quite a big amount of heat, well the northbridge is also on the water pump, cpu is r404 cooled with a vapo. (But NOT hitting 3.1ghz only 2715 )

[SlimHitman]

It will work on your Excalibur r9800 as long as the card follows the ATI reference design.

[(F)rossen]

The mail man was on time.

Rage3d and windows tells me that it is an 9800 pro, althoug the core speed is nonpro. why is that?

pro 380mhz
np 325mhz

The reason i bought this card, was an article, stating that it was mounted with samsung ram. NOT!!! It has infinion on it. So i guess that a hardcore memoc is out of the "?". Theres no heatsinks on the ram, but even if I put some on, would it be wize to do mods on the ram?

[SlimHitman]

Mine is a pro and Rage3d tells me it is 378/337.5.