MSI TwinFrozr HD 7950 Experiments

[Ket]

Not ordered yet, likely going to be the Vapor-X.

[Ket]

Alright, I ordered my new HD7950. I decided on the Sapphire HD7950 Vapor-X as after a lot of research it can be conclusively proven the card isn't voltage locked you just need to use the beta 4.4 version of TRIXX, its also seemingly possible to flash the HD7970 Vapor-X vBIOS to the card as the PCBs are identical - a nice compromise until I (or the authors of vbios editor) make a fully functional program for 7 series cards. The Vapor-X also has excellent VRM cooling.. with a little tweaking, so heres hoping my second outing with a HD7950 is much less problematic than my first outing

If anyone is wondering, I got my card from HERE 230 with free shipping, best deal for us UK folks I could find for a Vapor-X.

[BababooeyHTJ]

The main thing that would worry me about flashing a 7970 bios onto a 7950 is powertune. I heard that with 6950 when you flashed a 6970 onto it that the actual powertune limits wouldn't change. So its possible that you may run into issues with powertune at default settings.

[Ket]

I don't think powertune will be a issue as the 7950 vapor-x has powertune as well.

[tbone8ty]

filed some copper ramsinks down to fit on the memory chips. hopefully this will do something

[Ket]

Thats something else I didn't like about the MSI card - the retarded cooling design that leaves some memory naked. My new 7950 should arive either sometime today or tomorrow.

[Ket]

Well, my Sapphire HD7950 Vapor-X has just arrived. I'm a little excited by this card as a quick inspection of it shows that the card requires 2x 8 pin PCI-E plugs, not the standard 6+8 pin plugs. From what I can tell this revision of PCB must be super new as it doesn't resemble any 7950 PCB I've seen before. Maybe a new revision 7970 PCB Sapphire are also using for the 7950? Who knows, we'll need to see what PCB other Vapor-X owners have. Pics to follow soon.

[BababooeyHTJ]

The vapor-x is a custom pcb. Thats why it took so long for voltage control, I guess. It looks like there are pads for dual 8-pins in the techpowerup review. I doubt that there are any differences other than the connector itself.

I don't think powertune will be a issue as the 7950 vapor-x has powertune as well.

Yes but it doesn't effect the powertune limits so if you leave it at 0% by mistake there is a chance that it'll throttle clocks.

[Ket]

Custom PCB or not, theres no issue with plonking on a 7970 Vapor-X vBIOS as the two PCBs are identical. Even if Powertune doesn't work I don't give a flying crap about that as this card is going to spend its life @ +20% anyway Incoming pics folks, assuming they arent resized their super high-res.

Stock:











Idle and load temps were surprisingly high IMO, 37c and 67c respectively. VRM temps also climbed high when leaving Heaven to loop for about 10 mins, 77c. Temps were taken using the 2nd vBIOS which bumps the GPU clock to 950MHz. Before ripping the beastly looking (but a bit sh|t) stock cooler off I did do a quick dirty GPU OC test, I hit 1205MHz on stock volts. ASIC quality is 88.8%.


Modded:







No load tests yet but idle GPU temp is 32c and idle VRM temps 31c


Naked pics for vmod purposes:





Proper OC tests will follow.

[Ket]

Ok, this is a pain in the arse. The beta version of TRIXX won't adjust GPU voltage with my card so it seems Sapphire need to update the TRIXX software again to support this slightly different PCB compared to all the other Vapor-X PCBs. I'm going to flash the 7970 vBIOS to this card to see if that works around the problem.

[Andi64]

Didn't GHZ Edition BIOS have 1.25V? That should be enough for 1200-1300Mhz

[BababooeyHTJ]

Yeah, I wouldn't be going any higher than that on air anyways.

[Ket]

I tried the HD7970 vBIOS, and despite the fact the PCBs are identical for both Vapor-X models I was greeted with no display output. I've now tried 2 other 7950 Vapor-X vBIOSes and a 950MHz OC Edition vBIOS. The latter of all of those would seem to be the one to stick with right now as it allows for GPU voltage adjustments and memory voltage is higher as well. Default vBIOS with my Vapor-X is a pathetically weak 1.5v for the memory and GPU voltage adjustments are a no-go, period. Default memory voltage with the 950MHz OC Edition vBIOS is 1.6v, and of course GPU voltage works again.

Time to get down to some proper OCing now that crap is out the way with. I think I'll have to email Sapphire though to see if they can send me a proper vBIOS for my card, namely, one that isn't lame as sh|t.

ED - Seems I spoke too soon on that vBIOS, something in its configuration is slightly different and it causes the temp of one of the VRM sensors to think its well over 100c, which causes the GPU frequency to constantly bounce between 501MHz - 1255MHz. So now I'm using another vBIOS thats almost as new as the vBIOS that came with my card, memory voltage is still 1.6v but adjusting GPU voltage isn't possible again. If Sapphire can ever release a vBIOS that works properly on this card it has bags of potential, I'd guess 1300+ @ 1.2v

[Ket]

Ported discussion to HERE as I no longer have a TwinFrozr.

[BababooeyHTJ]

I'm hearing that the Sapphire 950mhz oc edition despite using a 7970 pcb won't take a 7970 bios. It appears that just because your card is using the same pcb doesn't mean that it'll use the same bios.

In the short time that I did try a reference sapphire 7970 bios on my TF3 a couple of months back it did work though.

[Ket]

I haven't had any problems using a 7970 vBIOS on this Vapor-X. Only oddity is VRM temp 1, it gets stupid high. ATM I'm using a slightly older Vapor-X vBIOS on my card, 015.025.001 instead of 015.025.099. This is because the former of those two vBIOSes has 1.6v set for the memory instead of a massively gimped 1.5v. Memory OCs are like night and day with that meager +0.1v. Its the difference between 1500MHz and 1650MHz.