Need help overclocking my 7900gt

zylander

Platinum Member
Aug 25, 2002
2,501
0
76
I just volt modded my evga 7900gt CO SC. GPU at 1.49v, mem at 2.32v. Right now the card is running at 500/1500, this card is suppose to run at 550/1580. When I bump the ram up to 1580, my computer freezes and the display starts going in and out and I end up havin to reboot. The card runs fine normally and the voltages are stable but I just cant seem to overclock it just a little bit, let alone get it to run at its stock speeds. Any ideas? Im using rivatuner to OC btw.
 

Hail The Brain Slug

Diamond Member
Oct 10, 2005
3,784
3,101
146
RMA to EVGA, your card is defective. They have released a new fixed version of the 7900GT's and GTX's that fixes the memory problems.

I went through 4 cards before they released the fixed ones, but HL2: Ep 1 made me happy. :D
 

TheRyuu

Diamond Member
Dec 3, 2005
5,479
14
81
Originally posted by: zylander
I just volt modded my evga 7900gt CO SC. GPU at 1.49v, mem at 2.32v. Right now the card is running at 500/1500, this card is suppose to run at 550/1580. When I bump the ram up to 1580, my computer freezes and the display starts going in and out and I end up havin to reboot. The card runs fine normally and the voltages are stable but I just cant seem to overclock it just a little bit, let alone get it to run at its stock speeds. Any ideas? Im using rivatuner to OC btw.

First off, way too much voltage IMHO on the ram. They should get high enough on just 2.2v alone.

Second, yes, your card is probably deffective. But just to be sure, reverse the memory vmod and leave the core vmod and see if that helps (you should be able to run @ 800mhz on memory at stock volts. (since thats what fixed my 7900GT)

Would you really RMA it after you vmodded it??? :p
 

1Dark1Sharigan1

Golden Member
Oct 5, 2005
1,466
0
0
Originally posted by: wizboy11
Would you really RMA it after you vmodded it??? :p

If he used the conductive pen method he may be able to pull it off. But still, a voided warranty is a voided warranty.
 

zylander

Platinum Member
Aug 25, 2002
2,501
0
76
I used the conductive pen voltmod. Also, following that write up, I raised the mem to 2.3 which is what it said, but Ill undo that and try it out at stock.

I was hopping I wasnt going to hear that its porbably deffective. This is the THIRD 7900gt Ive got, the first two were already defective, Ive already had to RMA it twice...Im getting sick of this ******. EVGA is not doing well in my book.
 

Bobthelost

Diamond Member
Dec 1, 2005
4,360
0
0
I'm not sure if the voltmod would invalidate the eVGA warranty, probably does, it's good but i doubt it's that good...

You're an idiot for trying to overclock when it didn't run at stock.




Was it a good idea? No. Were you right to start flaming? No. See you in three days.
AnandTech Moderator
 

Ulfhednar

Golden Member
Jun 24, 2006
1,031
0
0
Originally posted by: Bobthelost
I'm not sure if the voltmod would invalidate the eVGA warranty, probably does, it's good but i doubt it's that good...
Pen-modding invalidates the warranty on any graphics card, period.

This is simply another case of 7900 Syndrome, as some have come to call it.

 

nullpointerus

Golden Member
Apr 17, 2003
1,326
0
0
Originally posted by: zylander
I just volt modded my evga 7900gt CO SC. GPU at 1.49v, mem at 2.32v. Right now the card is running at 500/1500, this card is suppose to run at 550/1580. When I bump the ram up to 1580, my computer freezes and the display starts going in and out and I end up havin to reboot. The card runs fine normally and the voltages are stable but I just cant seem to overclock it just a little bit, let alone get it to run at its stock speeds. Any ideas? Im using rivatuner to OC btw.
Stock clocks on a 7900GT are 450/1320. You bought a factory-overclocked card rated at 550/1580. So yes, the card overclocks quite decently; it just won't handle being pushed any further than the factory overclock.

One problem with the factory-overclocked 7900GT's is that people assume its stock clocks are 550/1580 and expect significant overclocking above that, damaging their cards so that they can't even run at the factory overclock anymore.

Anyway, try reversing the vmod as wizboy11 suggested and see if that works.
 

zylander

Platinum Member
Aug 25, 2002
2,501
0
76
Originally posted by: XabanakFanatik
RMA to EVGA, your card is defective. They have released a new fixed version of the 7900GT's and GTX's that fixes the memory problems.

I know, this third one I jsut got was suppose to be one of the fixed ones. :(

Originally posted by: wizboy11
Would you really RMA it after you vmodded it??? :p
I might try haha.

Originally posted by: Bobthelost
I'm not sure if the voltmod would invalidate the eVGA warranty, probably does, it's good but i doubt it's that good...

You're an idiot for trying to overclock when it didn't run at stock.
I never tried to OC it, I tried to bump it up to its advertised speeds and when that didnt work I went back down.


Originally posted by: nullpointerus
Stock clocks on a 7900GT are 450/1320. You bought a factory-overclocked card rated at 550/1580. So yes, the card overclocks quite decently; it just won't handle being pushed any further than the factory overclock.

One problem with the factory-overclocked 7900GT's is that people assume its stock clocks are 550/1580 and expect significant overclocking above that, damaging their cards so that they can't even run at the factory overclock anymore.

Again, never tried to OC it past stock speeds.


Honestly Im probably just going to end up keeping it. I really dont want to deal with another RMA.
 

TheRyuu

Diamond Member
Dec 3, 2005
5,479
14
81
You should be able to RMA it. Just use alcohol to remove the core vmod. But like I said, reverse the memory vmod and run the memeory at 800mhz (1600 DDR rate). That might do the trick.
 

zylander

Platinum Member
Aug 25, 2002
2,501
0
76
Update just for the record. I did what wizboy suggested and reversed the memory vmod and the card is fine now running at 700/810.