Overclocking advice please, XFX 7950 DD
I have been trying to squeeze a bit more juice out of my XFX 7950 DD, which ships at 800 MHz. Only managed to get up to 950 MHz under normal voltage and keeping it stable. Voltage seems locked, certainly with oem software (catalyst) and MSI Afterburner, but managed to squeeze a much more acceptable 1050 MHz with Sapphire Trixx, with a not overly excessive 1.088 volts, stable with 3DMark suites of tests and gaming. I'm content with keeping this level (and not sure it'd take much more but bit concerned with vrm temps, in that I can't measure them, and there is no vrm cooling on this card). Core temps go up to 79* max under full load where I've set my fans go up dramatically. Would people think that this is within reasonably safe bounds? Grateful for some thoughts.
vmem said:the lack of vrm cooling concerns me too, especially given the chip itself is going up to 79 C (high, but within acceptable range). any chance you're willing to buy heat spreaders to stick on the vrms?
Hi, thanks for the reply. I certainly would consider it, not sure exactly what this would involve, would you stick them on the chips themselves with thermal paste? What sort of heat spreaders would be required, and would it make a considerable difference? Would consider a fan too if I knew what to do and how to do it!
to put on heat-spreaders for vrms, you would actually have to un-install your current cooler (which technically voids your warranty), then use thermal tape or some kind of hardening thermal glue to stick the heat spreaders on. it is generally considered a more 'advanced' type of mod. you'll be buying something like this:
aside from that, the airflow from your GPU's heatsink fans should be sufficient for cooling an generally having heat spreaders makes a big difference over not having them
That does look a bit more advanced than I would probably want to do with fan removal and warranty being voided.
I may try to reduce voltage slightly (and therefore temp) and see if I can still achieve 1050 MHz. During the 3d Mark testing it only hit 79 deg once and was only in the 70s for relatively short amount of time so I'm wondering if there would be more risk in taking apart and fiddling than ensuring decent fan speed at higher temps and monitoring core temp?
your GPU temp isn't the problem. when you increase the voltage, that adds load to the vrms. it is fairly typical to see vrms go above 100 c in this situation without proper heat dissipation, and you have no way to monitor this. I'm not trying to scare you into not overclocking your card, by all means do so, and 1.088v really isn't excessively high. as I mentioned before, it is just a personal concern, not necessary a bad thing. Actually, the lack of VRM cooling on the XFX card was the very reason I bought a sapphire dual-X back in the day
Got core down to 75-76 deg max on a 99% effort 3DMark test with decent fan speeds.
I looked at how the card is built and there's thermal pads between the vrms and the fans, not entirely sure how an additional fan would help tbh as the existing gpu fans cover the vrm area.
What would probably be a good idea is to have a sapphire trixx profile for o/c'ing and a separate one for using base voltages and speeds so I only stretch the card when required. Grateful for any thoughts.
very nice! those are nice temps for 3D mark
it's also good that there are thermal pads on the vrms, that should at least help a little bit
I don't think using a separate software for gaming performance helps as the only concern here is load temperatures/voltages. the GPU itself operates at lower clocks and voltages for most tasks short of benchmarking/gaming/3D rendering. tho honestly at your current temps and taking thermal pads on the vrms into accound, I'm not too concerned
Thanks again vmem, yea fair point on the using separate software - the only reason I use sapphire trixx is that it's the only program that let's me increase voltage on the xfx 7950. But I may as well just leave it on that profile and it's only when I push it that it'll be stressed. It's made a considerable difference in terms of benchmarking up from 4400 on 3DMark to 6800. If I push much more voltage through then it throttles back, and the temps would be too high anyway so I'll leave it at that now. Cheers mate, I'll add your help as the chosen solution.