T61 GPU chips compatibility

[GunslingerThink]

So I want to replace the graphic chip of my T61. It is originally Quadro NVS140M so it's some G86 chip. I know that all chips older than mid-2008 are no good, but I was wondering which G86 model numbers I can use other than exact the original model (I think it's 700-something). Can I use any of G84 chips on this motherboard?

[ajkula66]

So I want to replace the graphic chip of my T61.

You have re-balling equipment ?

Can I use any of G84 chips on this motherboard?

That would be an exercise in futility, since all of them suffer from the same defect...

[GunslingerThink]

You have re-balling equipment ?

No, but I'll find someone who has.

That would be an exercise in futility, since all of them suffer from the same defect...

Even the newer ones? I've seen pictures of G84 with production date up to 2012. What about G86 then?

[Screamer]

but I was wondering which G86 model numbers I can use other than exact the original model (I think it's 700-something).

The G86-740-A2? If I am not wrong, that is the Quadro NVS 140M.

I suppose that the G86-731-A2 and the G86-730-A2 can be installed to replace a dead G86-740-A2. Take this with a grain of salt, though. I have no idea if they are electrically compatible.

Can I use any of G84 chips on this motherboard?

This is a G86 motherboard, right? In that case, no. There is a specific resistor configuration that has to be present on the motherboard, in order to make a G84 graphics chip function on a G86 motherboard.

Any G84/G86 graphics chip that has a date code of 0831 and above are guaranteed to be free of the low-quality underfill, but please be aware that they may be relabeled for no apparent reason (RealBlackStuff has seen some of them).

[RealBlackStuff]

If your T61 is a 14.1" 4:3 (non-widescreen), it may be cheaper (and definitely easier)
to replace the motherboard with a 44C3924 as explained here: https://www.theboardroom.info/t61motherboard.html
Forum member TuuS has these in stock.

[wujstefan]

If your T61 is a 14.1" 4:3 (non-widescreen), it may be cheaper (and definitely easier)
to replace the motherboard with a 44C3924 as explained here: https://www.theboardroom.info/t61motherboard.html
Forum member TuuS has these in stock.

Way cheaper. Unless your re-balling cooperator volunteers.
I have found trouble sourcing 14,1 16:10 nvidia mobos though.

[atagunov]

BTW is video RAM inside a G84/G86 chip or outside on the motherboard (Thinkpad T61/T61p)?

Context: I've been trying to figure out what G86-731-A2 chips are and if the RAM is inside and if it is how much of it is there.

Hmm if the info comes from https://www.badcaps.net/forum/showthread.php?t=21001 then we have
.

part.n     name             converter mhz-core mhz-shad mhz-mem  mem bit
G86-731-A2 GeForce 8600M GS 16        400      800        600         64
G86-740-A2 GeForce 8600M GS 16        450      900        600         64 
G86-741-A2 GeForce 8600M GS 16        450      900        600         64 
G86-751-A2 GeForce 8600M GS 16        450      900        600        128
G86-771-A2 GeForce 8600M GS 16        600     1200        700        128

.
which makes it a little less clear why G86-731-A2 seems to be recommended over G86-741-A2 to replace a dead G86-740-A2.

Okay if the frequencies are set externally perhaps it may be getting just a little overclocked and still work ok..
Still not sure why it'd be better than G86-741-A2

I'm still wondering where the RAM is and if any higher spec G86 can replace a G86-740-A2. I guess any 256Mb one would be good enough btw it seems more fun to mess with G86 (NVS 140m) than G84 (FX570m) because of lower power specs

[kfzhu1229]

I remembered I read somewhere that the 7x1 chips are also manufactured with a smaller process and has less heat output. At least that's true for the G86-621-A2 on a Latitude D630 which even with a crappy Dell thermal pad it runs cooler than the board with the 620 chip that eventually failed.
Did Lenovo even bother using the G86-741-A2 chips for any of it's safe datecode mobos?
And also the VRAM is soldered onto your motherboard and I dont recall there is a NVS140M for ThinkPads that have 256MB of VRAM and only the 15.4" Quadro FX ones come with 256MB
As for if you wanna try also upgrading the vram, you need to make sure you have 4 ram chips as 4 64MB chips is what the 256MB version of NVS140M uses

[shabba]

This looks to be an informative thread. I'm going to keep an eye out here... very curious about how this might pan out.

[ThreeIguanasPerSecond]

is video RAM inside a G84/G86 chip or outside on the motherboard?

on the motherboard or daughterboard, all G84 and G86 chips did not have an on-package VRAM variant.

I've been trying to figure out what G86-731-A2 chips are and if the RAM is inside and if it is how much of it is there.

IF we were to trust the specifications coming from badcaps (which i don't), it's a GeForce 9300M G.

on the presumption that the specifications are incorrect, it's either a GeForce 8400M G/GS/GT or a 8600M GS or a 9300M G, or a Quadro NVS 130M/135M/140M or FX 360M. which can it be depends on the number of CUDA cores/unified shaders, texture mapping units, render output pipelines, memory bus width, core frequency, shader frequency, and memory frequency.

Hmm if the info comes from https://www.badcaps.net/forum/showthread.php?t=21001 then we have

part.n name converter mhz-core mhz-shad mhz-mem mem bit
G86-731-A2 GeForce 8600M GS 16 400 800 600 64
G86-740-A2 GeForce 8600M GS 16 450 900 600 64
G86-741-A2 GeForce 8600M GS 16 450 900 600 64
G86-751-A2 GeForce 8600M GS 16 450 900 600 128
G86-771-A2 GeForce 8600M GS 16 600 1200 700 128

nearly all of the chips are identified incorrectly, the only exception is the G86-771-A2 as it has the correct specifications to be considered as a GeForce 8600M GS. now you can probably understand why i don't trust them.

which makes it a little less clear why G86-731-A2 seems to be recommended over G86-741-A2 to replace a dead G86-740-A2.

you just answered your question:

Okay if the frequencies are set externally perhaps it may be getting just a little overclocked and still work ok..

indeed, by the GPU's video BIOS that is either integrated into its daughterboard via a BIOS chip or integrated along with the system's main BIOS.

Still not sure why it'd be better than G86-741-A2

badcaps recommended the G86-731-A2 chips, right? if my assumption is correct, the main reason might be due to availability issues, cost, or the fact that these chips just happen to have a higher chance of being made later than the risky old chips which still has the dreaded underfill like what Screamer mentioned in his post. thing is, i don't know what kind of folks i'm looking at in badcaps, so i'm just going to take it as they have some technical competency and are not wholly incompetent.

if any higher spec G86 can replace a G86-740-A2.

the VBIOS controls the clocks, but certainly NOT the memory bus width and other specifications that can't be changed by it. so yes, you can. but if you have a chip which has a 128-bit memory bus width as opposed a 64-bit bus, you have to account for that difference by making sure that the VRAM chips used will add up to that bus width. if you use the wrong ones or you're stuck on a board that doesn't have a second 64-bit wide channel, you're going to get a 64-bit memory bus instead of the specified 128-bit memory bus.

I remembered I read somewhere that the 7x1 chips are also manufactured with a smaller process and has less heat output.

they're not, they have the same physical die measurements as their 7x0 counterparts. if they were smaller in comparison, then i'd believe they have a smaller process, but they don't. it's likely that they were binned differently or had changes made to the die's characteristics to run cooler at the same voltage and speed.

if you don't get it, think about the Pentium 4's numerous steppings. now let's say that there are two CPUs that are both similarly clocked and set at the same voltage, for reference: SL5ZH (B0 stepping) and SL6WZ (D1 stepping). all of them are stuck at 1.2GHz and have a core voltage of 1.2V, which do you think runs cooler?

As for if you wanna try also upgrading the vram, you need to make sure you have 4 ram chips as 4 64MB chips is what the 256MB version of NVS140M uses

you can't upgrade them to 256MB if there isn't an empty ball grid for a VRAM chip to be mounted on, don't forget that. then you'd need to assume the empty ball grids are actually connected to the GPU, because there's a chance where they're simply left there unconnected. some motherboard vendors do this, some don't.

[kfzhu1229]

they're not, they have the same physical die measurements as their 7x0 counterparts. if they were smaller in comparison, then i'd believe they have a smaller process, but they don't. it's likely that they were binned differently or had changes made to the die's characteristics to run cooler at the same voltage and speed.

Okay yeah I found it now it is several Chinese sources but they claim it's a die shrink from 65nm to 45nm which I think is BS. I wasn't able to find any English sources with links that are not dead about this stuff. The 135M and 140M's I am familiar with all have 80nm process and the newer NVS 160M has 65nm, so I think what happens is the 6x1 and 7x1 chips might be with a 65nm process instead. That's entirely possible because when the 65nm process is mature enough in like August 2008 it is cheaper for them to use 65nm instead of 80nm. Unlike the T/R61 discrete chips the Dell revised ones that I have come across all have the 6x1 and 7x1 chips with glue on the corners of the chips and even revised boards for the older G72M (NVS 110M) generation of chips exist.
That said it is entirely possible those are just speculations and didn't actually end up like that.

you can't upgrade them to 256MB if there isn't an empty ball grid for a VRAM chip to be mounted on, don't forget that. then you'd need to assume the empty ball grids are actually connected to the GPU, because there's a chance where they're simply left there unconnected. some motherboard vendors do this, some don't.

What I meant is if you have a 2 chip configuration I don't think it is possible to upgrade even if you take the chips out. At least with the 4 chip configuration you can take all the chips out and replace them with 64MB chips instead assuming the BIOS likes it.
Don't think Lenovo would leave 2 empty soldering pads for the VRAM chips for their 128MB versions and I believe using 4 32MB chips is cheaper for them.

[atagunov]

Thx a bunch for info! My 14" 4:3 T61 NVS 140M 128Mb mobo is still in China; only got two crappy photos. I started looking trying to make out how many chips there are. I have found some other photos online. But it's a bit hopeless There can be more chips under mylar and on the back. Need to wait..

BTW this review of a T61p FX570M/256Mb VRAM has got a high-res photo of the mobo front side. Think I can make out Hynix HY5RS123235B FP-14 on that chip which makes it 700Mhz 536,870,912 bits = 64Mb. Then there's another similar chip sticking from under mylar. Other two are probably either under mylar too or on the back.

[RealBlackStuff]

Don't know if it helps, but check the pic on my webpage: https://www.theboardroom.info/t61mobo.html

[kfzhu1229]

BTW this review of a T61p FX570M/256Mb VRAM has got a high-res photo of the mobo front side. Think I can make out Hynix HY5RS123235B FP-14 on that chip which makes it 700Mhz 536,870,912 bits = 64Mb. Then there's another similar chip sticking from under mylar. Other two are probably either under mylar too or on the back.

Just so you know 14" and 15" boards may have major differences in terms of these sorts of things due to space restrictions.
I highly doubt the 14" versions would have 4 VRAM chips because no 14" T6x ever come with 256MB of VRAM.

[kfzhu1229]

Okay so I would like to update on the whole G84/G86 chip situation with these models from more research from Chinese sources.
So for the NVS 140M 128MB used on T61 models, there are 3 different chips. The first one is obviously the unsafe one. The second one is the safe one but with also G86-740-A2 but has revision 01R and a "safe" datecode, and the third type is the completely revamped G86-741-A2 with white coloured glue around the die instead of black and features 45nm process instead of the older 65 if this source is accurate:
http://www.whjldn.com/122.html
Unfortunately for T61 models, it seems like NVidia started pushing out the xx1 variants of the lower end chips first, so NVS140M kinda missed out on that until one and a half years after production was ceased for T61 models.
The second type is exactly as what RBS mentioned:
https://forum.51nb.com/thread-1296692-1-1.html
For the third type, on the Chinese 51nb forum, there are lots of ppl that opted to reball and swap the chip to G86-741-A2 themselves, such as these here:
https://forum.51nb.com/forum.php?mod=vi ... 0%D7%BD%BA
Another but reball and swap to a safe G86-950-A2 and it seems to work fine:
https://forum.51nb.com/thread-1262935-1-1.html
For reference here is such a service offered to swap the chips on your motherboard for ￥450, ￥550 buying an entire motherboard with the chip swapped (this is for G86-771-A2):
https://forum.51nb.com/forum.php?mod=vi ... 0%D7%BD%BA

As for the difference of black and white glue, from what I have from my Dells, it is very much in line as both of my unsafe chips have black glue around the die and all of my safe xx1 chips have white glue instead.
Dell switched to the xx1 series very soon unlike ThinkPads, probably because they use a lot more entry level chips like the NVS135M and FX 360M and the xx1 chips for those come much earlier than the higher end ones.
I know my safe ones are safe because they are replacement motherboards as the manufacturing date is much later than the ship date indicated by the service tag and each of them have one additional year of warranty due to this replacement.
Here I have a gallery of 2 unsafe black glue chips and 3 safe white glue chips from my Dell motherboards:
https://imgur.com/a/eBC1PdV

So in summary, what I have learnt is that the safe chips have a later datecode and a much fatter looking font for the model number, and the later totally redesigned xx1 chips have those on top of using white glue, potentially a die shrink and of course the model number change itself.
Note that this does NOT account for counterfeiting such as etching different model numbers and such, which is apparently a common scam to do in China.