SGI: Hardware

Hi all

Ive got a question about over clocking (please read further) the cpu to 200 mhz . I can see it has been done but after checking out a few things I am more confused about what seems to be one small detail.

The german page ( http://hardware.majix.org/computers/sgi ... ning.shtml ) which involves removing & changing two resistors. One of the resistors is replaced with a 4.7 k ohm resistor. The thing which has caused me confusion is while I was reading a post about using a O2 cpu on a indigo2 question, and that answer is isn't possible for a number of reasons, different voltage being one of them, and now Im wondering if its such a good idea... sort of thing

On the german article it reads

" This guide explains how to get a 200MHz CPU Octane R10000 work in an indigo ². This has been done and documented by Andre Schäfer . This has been done and documented by Andre Schaefer. Currently only a german Version is available. Currently only a german version is available."

Which makes me think ok, they are using a Octane cpu module, and the different resistor is to compensate for the voltage difference somewhere (although I don't think the resistor is handling the current, its too small, but thats all speculation.

... It also reads on the next line

Umbau eines Indigo2 R10k/175MHz CPU Moduls zu einem R10k/200MHz Rebuilding an Indigo2 R10k/175MHz CPU module to a R10k/200MHz

Which makes me think were back to using a Indigo2 R10k/175 mhz cpu. So what one are we using ...*hmm*.

On the nekochan.net there is another example of the change, however two resistors are moved from the bottom to the top of the cpu module.

If this is the case and the resistors can be re-used, why did the other site not just re-use them. That's really what i'm wondering.

http://www.nekochan.net/wiki/gallery2/v/SGI_Photos/album56/
see
http://www.nekochan.net/wiki/gallery2/v/SGI_ ... k.jpg.html
and
http://www.nekochan.net/wiki/gallery2/v/SGI_ ... k.jpg.html


Does anyone have any experience doing this? Or insight on anything they have heard but I couldn't find during my searching?

Any info is appreciated

Thanks so much

Jonathan

I did it. The R10000 processor at 175 and 195MHz uses the same voltage across all platforms. For the modification you use your Indigo2 PMT5, and the only reason you get a Octane or O2 PM10 (or whatever the O2 name for the module is) is as a processor donor for the R10000/200 rated chip. The resistor mod (on your I2 PMT5) changes the clock multiplier to 4x rather than the 175MHz' 3.5x.

If you want to risk it, you can even overdrive your existing PMT5's R10000 (they're rated at 180MHz or better) and dispense with the Octane or O2 module altogether.

R10000 >= 225MHz are a no-go, though, because of the different voltages.

Mine worked just fine for several years, but after that I decided that driving parts beyond their ratings just wasn't worth it for the minor boost it gave. I didn't get the proper 200MHz - rated CPU, though, so it was more of a risk.

Anyone here know why SGI tends to underdrive their processors (R10000 at 195MHz rather then the max rating of 200MHz, and I've seen a 4D/35 with a full 40MHz-rated R3000)?

Hey thanks so much for the reply!

SAQ wrote: I did it. The R10000 processor at 175 and 195MHz uses the same voltage across all platforms. For the modification you use your Indigo2 PMT5, and the only reason you get a Octane or O2 PM10 (or whatever the O2 name for the module is) is as a processor donor for the R10000/200 rated chip. The resistor mod (on your I2 PMT5) changes the clock multiplier to 4x rather than the 175MHz' 3.5x.

Which resistor MOD did you use? I see the two, and still I'm not sure what one is the correct one .... Or are they both the same


So I take it the PMT5 is the sort of cpu board + socket. I'm guessing its possible to setup my 175 to run like a 195 instead of 200 also, if I get the resistor settings for that... ?

SAQ wrote: If you want to risk it, you can even overdrive your existing PMT5's R10000 (they're rated at 180MHz or better) and dispense with the Octane or O2 module altogether.

I don't quite understand what you mean by risk it, are you saying to use the Octane or O2 module (cpu and board) or just cpu ? If I used say a 200 mhz cpu, technically, I wouldn't be over driving anything, and that cpu would go on my pmt5 indigo2 board?

SAQ wrote: R10000 >= 225MHz are a no-go, though, because of the different voltages.

Mine worked just fine for several years, but after that I decided that driving parts beyond their ratings just wasn't worth it for the minor boost it gave. I didn't get the proper 200MHz - rated CPU, though, so it was more of a risk.

Execellent, 200 should be more than enough. Perhaps I can just get a 195 mhz chip and run it at 200 w/o and serious risk. I've done some checking and my 175 mhz cpu @ full load doesn't seem to even get hot to the touch. I think to be safe before I fiddle I will reapply some thermal paste and keep a little monitor handy to keep an eye on it... or just get a 195 if I can find one! , or perhaps even a 200!

SAQ wrote: Anyone here know why SGI tends to underdrive their processors (R10000 at 195MHz rather then the max rating of 200MHz, and I've seen a 4D/35 with a full 40MHz-rated R3000)?

Hopefully someone can shed some light on your question, I really have no idea, unless they felt that 5 mhz under would provide better reliability...

One other question

Does anyone have any info re: what resistors set what multiplier. I ask because If I get a 200 mhz cpu I would like to try to achieve 220, or 225 mhz.

Thanks

Jonathan

SAQ wrote: Anyone here know why SGI tends to underdrive their processors (R10000 at 195MHz rather then the max rating of 200MHz

Dunno, but even at 195MHz they weren't very reliable when they just came out.
I had an account on a (then) brand new PowerChallenge (simple user) with ~ 12 x R10k's and during the first year the system was down quite often because a CPU had failed.

SAQ wrote: and I've seen a 4D/35 with a full 40MHz-rated R3000)?

4D/35's were dangerously close to the limit, thermally speaking. Maybe an underclocked 40MHz chip ran a little cooler? Maybe they didn't have any 36MHz chips left at some point? Who knows ...

jan-jaap writes:
> Dunno, but even at 195MHz they weren't very reliable when they just came out.
> I had an account on a (then) brand new PowerChallenge (simple user) with ~ 12 x R10k's
> and during the first year the system was down quite often because a CPU had failed.

Many probs with Onyx/Challenge boards tend to be cache-related. Whatever it was, I think it
must have been sorted by the time R10K/195 was used in Indigo2 because bad R10K I2 CPUs
are very rare. I think I've only ever encountered just the one over the years.


> 4D/35's were dangerously close to the limit, thermally speaking. Maybe an underclocked 40MHz
> chip ran a little cooler? Maybe they didn't have any 36MHz chips left at some point? Who knows ...

I can see it now, people overclocking the PS1s to 40MHz.

Ian.

i was tempted to overclock, but humm, i see here and there 175 modules for ~10$ that can be easily overclocked to 200, but on the end ... 195 or 200 is not much diff right ... you got that right on that german article ... it`s strange the author talks about usual 175-> 200 overclock of I2 module, but in the english header majix site talks about octane cpu at 200 Mhz ? ... then again is much diff 195 I2 or 200 Octane cpu ?

... i readed on some news groups (google ?) that time ago on eBay appeared an real 250 Mhz I2 R10 impact - that was confirmed, not R4400 at 250 but real R10 at 250, who, how and when is not known ... the seller only gived the hinv that showed R10 cpu working at 250 that was it, and this can be one improvement worth future exploration ...

... too bad I2 not have same CPU slots as the Octane does, then overclock will be probably more easy ... i even thinked if is near possible to put one dual 175 or 195 Octane module into I2 ? probably not ... yes ? who knows ... maybe ... that will be one REAL improvement ...

cheers

Hey all

Just wanted to follow up and firstly say thanks to all who replied! And also give an update on my progress. I decided to try the overclocking method in the nekochan wiki, which was successful 100%. After some more reading I am 99% sure the other article is taking a 200 Mhz from an O2 and using it on the circut board the cpu is fixed to for the indigo2. I think this circut board for anyone else who is/was lost is called / referred to as 'pmt5'. Anyhow it sort of started off to a rough start, as when I tried to remove the two screws on the connector side of the cpu which hold it down in place... well they were um stripped . I tried to remove them carefully but it backed the standoff off the screw on the underside of the motherboard, so this simple procedure turned into an operation. Anyways I removed the standoff's and re- threaded them, as well as the screws. There was enough meat left and I was able to carefully line things up so that I retraced the existing threads and cut a bit of a new one. What an experience, I think a monkey assembled my I2.

Pic of getting ready to fix the screwy screws.

* These may come up slow - be patient its hosted on a computer of the dinosaur era - Ultra1 creator... 167 mhz.

**more are available in the gallery.. ( http://jcbox.dyndns.tv/gallery/I2 )




I proceeded to take apart the cpu module, when splitting it the cpu was attached to the top heat sink - no surprise. I stood the heat sink sideways and gently tapped against the cpu with a plastic poker, it came loose and the heatsink pad was perfectly preserved.

I was able to remove / re solder the resistors no problem, and re assemble the cpu module.

Initially when I powered the system back on, the first thing I noticed was that the system fans were all running faster... not sure if its coincidence or not... So I whipped up a little extra cooling for certain crispy critters. Running the cpu w/o the extra cooling didn't feel hot to the touch, but was certainly warm.

I had to relocate the speaker to install the 2pack of the small fans. Since they are small, and drawing 1.14 a @ 12 volts, you can imagine the annoying jet engine sound they produce when operating, which is why I opted to use 5 volts. I will rig up a small controller to bring them up to 8v or so if things start to get toasty...

pix:


and


Anyways its all working now. I've ordered an O2 200 mhz cpu which I will be installing so if anyone has any picture requests, now is the time to ask!

Jonathan

Congrats!!

- but what you done ? you put O2 200 cpu into I2 module ? right ?
- i see you are cooling your SI - is that hot ? i wanted to do this with my MXI but there`s no room for any fan ...

cheers

Hey

I might have left out some info ... I posted late last night sort of a sleep already lol.

cybercow wrote: Congrats!!

- but what you done ? you put O2 200 cpu into I2 module ? right ?

Not yet, it is just the R10K 175 mhz cpu right now. I have ordered a O2 200 mhz R10k cpu from ebay and im waiting for it to arrive. At that point im just going to swap it in... I was just trying to say I think thats what the german page was describing he did. The only part that has me concern'd at the time was the different uses of the resistors... and that perhaps somehow they also changed the voltage signal to the voltage regulator ... but I don't think thats the case...

cybercow wrote: Congrats!!

- i see you are cooling your SI - is that hot ? i wanted to do this with my MXI but there`s no room for any fan ...

cheers

For the fan those aren't that thin (the ones in the picture), but some of the amd (iirc) cpu's had really thin "green" colored plastic fans, mind you they were sleeve bearing, but ok. They were about 3mm thick, which makes them very useful... I can pick them up at the local surplus store here there are boxes of em...

The SI is actually really hot to the touch, I dropped the card down one slot level and made small standoffs from plastic to put in the heatsinks and fan holes to hold it on that angle. I wouldn't say its required, it's just more of my nature to be more safe than sorry... I tend to perhaps over due things a bit P.s. I have since changed my SI for a high impact. . . It doesn't seem to run as hot as the SI... I'm hoping to find a Max Impact then I can keep that cool too!

Same thing with the cpu, with the stock cooler, it wasn't *hot*, but I like to make sure it stays that way...
I think using the 200 mhz cpu instead of the 175 over clocked would also run cooler.

Does anyone have any of the thermal (W) data sheets for these suckers?

Thanks,

Jonathan

jc179 wrote: The SI is actually really hot to the touch

Solid Impact is *nothing*

Try MaxImpact, or better: MaxImpact with the TRAM option cards I guarantee you it puts out two or three times more heat than Solid Impact. It's the sort of thing that noticeably warms up the room it's in. The fan in the graphics card cage can keep up with that, plus whatever you have installed in the fourth slot. OK, barely keep up

Anyway, I wouldn't worry about an SI card.

... yes ... thinked several times of some system to add extra cooling the Max Impact cardset, but there is not room for one finger when you have for example some other card in the 4th slot ... the best thing would be put the fan on the left side spot of the boardsets ... specialy because the TRAM`s modules .. you know ...

anyone some idea here ?

jan-jaap

The funny thing is the High impact I have now runs a lot cooler than the SI card... this is of course under load.

I believe you when you say the Max Impact is hot, I bet its incredibly hot !

I'm still trying to find one working or not ... Do you know of anyone who'd have one they would be willing to part with or any defective tram modules ?

cybercow,

The only idea I have is to remove the metal side cover which you pull down to access video cards. That would provide enough room to install a cooling fan. As it is right now you might be able to get in one of those super thin cpu fans and mount them in there. I have one somewhere around here and was contemplating trying it out if I can find it ... If im successful i shall post !

maybe

http://item.express.ebay.com/Computers- ... xpressItem
or similar.

been out of country for a while.

The PMT5 is the plug-in CPU and cache daughterboard for the Indigo2 IP28 (it has the heatsink and fan on it). Not sure if you figured this out, but when you get a O2 processor module (or the Octane module, which is a PM10 (single processor) or PM20 (dual-processor module)) you open it up and remove the 200MHz rated R10000 LGA chip and put it in your original Indigo2 PMT5 processor module.

I wouldn't recommend trying to go over 200 on a first-gen R10000. When they boosted the speed they tweaked the chip a bit, I'm not sure if it was a different process or not, but they did have to do something. The fact that they never released chips rated faster than 200 indicates that they didn't get enough running reliably to make it worthwhile. They probably ran into timing errors or thermal problems.

Hey

thanks, thats very good info you have there . I will just keep it at 200 then once I get the 200 mhz chip

Thanks for clearing up the daughter board info as well!

Jonathan

Hello

Today i recive CPU module O2 r10000 250Mhz, i leave the cpu and i put in my original module I2 175Mhz and work the CPU, i check the oscillator mount in the module I2 is 175Mhz, i buy tomorrow one oscillator 250Mhz cmos smd and remplace when i recive.

If work i post all.

Thanks

Perfect hack the module board I2 195MHz to 250MHz R10000sc 2.6 Vcc.

Post video youtube.

The next week i recive other r10000sc 250MHz, one r12000 300MHz for test, and couple module indigo2 later i make photo all part how to hack.

Video

http://m.youtube.com/watch?v=_XUCw-OePCg

Thanks

What are you doing to compensate for the different voltages? Your PMT5 is giving the R10k 3.3V, and as you noticed the >200MHz R10ks use a 2.6 V supply. Not sure about what the logic output levels are and if they're different.

Also note that the cache is driven off a programmed divider - you might (probably will) need to change that divider or change the cache chips so the BCache can keep up with the new processor.

Hello

Need to put max. 3.0 volt in vcc r10000sc 250mhz work fine this voltage ,support max 3.0 V, test couple day render 3d, and not crash.

Change one Ic, one resistor smd and the smd oscillator.

Multiplicator 4X60mhz = 240mhz but the ic u12 need to hack.

I test yesterday overclock the R10000sc 250mhz to 300mhz and work but after 5 minute crash the prom, possible the r10000sc overthermal problem. Put off the indigo2 wait 5 minute and work to 300mhz.

When i finish all test i post all.

Later i test R120000.

Thanks

Sorry for my english but i'm Italien.

tooR wrote: Hello

Need to put max. 3.0 volt in vcc r10000sc 250mhz work fine this voltage ,support max 3.0 V, test couple day render 3d, and not crash.

Change one Ic, one resistor smd and the smd oscillator.

Multiplicator 4X60mhz = 240mhz but the ic u12 need to hack.

I test yesterday overclock the R10000sc 250mhz to 300mhz and work but after 5 minute crash the prom, possible the r10000sc overthermal problem. Put off the indigo2 wait 5 minute and work to 300mhz.

When i finish all test i post all.

Later i test R120000.

Thanks

Sorry for my english but i'm Italien.

It's not worth the risk of taking apart the PMT5 again. R12k requires PROM upgrades over R10k, and they're not present in Indigo2.