Just seen these CPUs. 133 Mhz x 16 = 2133Mhz. Sounds like a perfect upgrade option for my old 266 fsb mobo.
Anyone has more info on these 4Cs? What other ratings are available? Guess they are simply Thortons but with full 512 KB cache (no need to connect L2 bridges manually -)).
Your other choices are the mobile XPs (Barton) which are also 133 Mhz FSB, and 512 MB L2 Cache. The Mobile XP2200+ and up have high multipliers enabled. Tricky in some legacy motherboards. They overclock like crazy and have unlocked multipliers.
@TheRod
the link you gave is i think for ordinary 333 fsb barton with low multiplyer (4D)and clocked at 2.083. but that one wouldnt work well with low fsb. the one i found is 2133 mhz (in some price lists erroneously described as 2.083). guess this one is quite a rare thing these days, dated 0328 .i am told it may be one of those oem bartons used by pc manufacturers like hp and compaq in some of their models.
@phsstpok
i have msi 6378 v.3 officially not supporting anything better than t-breds. however for almost a year now i been using 2400+ thorton (other words half-cache barton) without a prob. this new 2800 could give me full 512k cache without having to tweak hardware (l2 bridges) on my 2400 and higher multiplyer too. i was wondering if there are any even higher ratings/multiplyers of these 4Cs.
is it possible to use mobile XPs in desktops? is support by bios required?
is it possible to use mobile XPs in desktops? is support by bios required?
Yes and no. If your mobo gives access to multipliers, and v-core, you can drop an xp-m in, and run it at 2.2 ghz or better. You may have to adjust the v-core
I've heard of people putting the mobile Bartons into the Epox 8KTA3PRO (which is what I have) with good results. That's a KT133A motherboard. Your MSI 6378 has a KLE133 chipset which came later but was basically the same but with integrated graphics.
If you presently have a thorton XP2400+ working in your mobo then you then you already have the high multipliers working (15X in your case) and 133Mhz FSB. I think you would have good results with a Mobile Barton.
I see you found a Barton week 0328 or a variant there of. I've never heard of a "4C". Being week 0328 though, I'm wondering if it's unlocked.
You won't know if it will work until you try it.
Functionally it seems to me like it would be the same as the Mobile Bartons. Same bus speed, 133 Mhz, and same size cache, 512 KB. I wonder if it's just an early in-house designation for the same thing. You know the "4C" designation kind of reminds me of the old "Athlon 4" designation which were mobile Palominos. Maybe the "4C" means it is a mobile.
The BIOS being able to identify the CPU isn't always required for it to work. Plenty of owners of mobos with legacy VIA chipsets have had Tbreds, Bartons, and now Mobile Bartons running. All the time their system report the infamous "Unknown CPU".
I repeat, you won't know unless you try it or hear of someone else who has tried it.
my 6378 supports XPs (officially) up to 2600+ meaning multiplyers up to 16x. v-core is not adjustable so it'd probably just give the same 1.65v to a mobile version which would be ok for say AXMA3000F(K=1.65)T4C but what about 16.5 multiplyer here?.. For say AXMG2600FQQ4C - 1.65v for a 1.45v cpu would be quite a challenging operating condition i guess. so this 2800 4C seems like a top competitor here with maximal acceptable multiplyer, right voltage and maximal cache for socketA cpus.
also this 16.5 thing above makes for asking a good question here. is there any chance at all that a system with an 'oversize multiplyer' cpu might actually still be able to boot? i'm asking cos my mobo's cpu/fsb ratio is not adjustable so what if i get myself say a 16.5x or some 17x processor?
i was also wondering if someone could explain to me what's this 'FSB Auto detect' feature in mobile XPs. do they like adjust their multiplyer accordingly after detecting fsb to keep their internal clock constant or smth like that?<P ID="edit"><FONT SIZE=-1><EM>Edited by nise on 11/24/04 05:00 PM.</EM></FONT></P>
If your mobo uses auto-detect only for processors, steer clear of the xp-ms. They default to 800mhz. See if there is a screen that would allow you to change the multiplier, if the chip allowed. If there is, try upping your multiplier to 16. Many of the old 2400+s could do that no sweat. No point in upgrading if it does.
Your getting into a lot of "what ifs" to which I don't know the answers, not for certain.
My thoughts, in no particular order.
Desktop systems interpret the voltage ids, VIDs, of mobile CPUs differently than laptops. That's why the 1.45 V mobiles POST at something like 1.6 volt by default on desktop motherboard. Not a problem on motherboards that can set Vcore manually. I don't think it's an issue with Mobile Barton which seem to do pretty well up to 1.75 volt, even 1.8 volt. You're taking big risks if you set Vcore higher than that for sustained periods (IMO).
Your motherboard has a max multiplier? That mightmax only be documented because the chipset was designed in the Palomino days, when I think 13.5x was the highest.
Adressing that by example, my previous motherboard, an Abit KT7 with a KT133 (not KT133A) chipset had a max documented multiplier of 14x. Yet I've run my mod'd Tbred up to 21X multiplier and POSTed my board up to 23X. This was with FSB of 100 Mhz.
So don't take the multiplier max as an absolute limit it depends.
Now for the gotcha's. The only reason why my mod'd XP1700+ worked on my KT7 so easily (in my opinion) is that I have a 1.6 volt version instead of the later 1.5 volt versions. This is a factor because the KT7 defaults to a 20X multiplier when any unlocked processor with a high multiplier (13X or higher) is installed and 20 x 100 is a bit of overclock stretch for an early the Tbred B at 1.6 volt nevermind 1.5 volt. Each time I cleared CMOS I had to quickly increase Vcore. I had to jump into BIOS setup quickly before the system crashed. At 1.85 volt 21X was no problem.
How does one do it when multipliers are limited to 13X? These old motherboards can't manipulate the higher multiplier bit, the 8X bit, but if the bit is forced either by mod'ing the L3 bridge on the chip or by mod'ing the socket then the CPU multiplier remaps take over.
The remaps are kind of like that of the old K6-2. Set the multiplier to 2X and 6X is interpretted internally. On Tbreds, unlocked Bartons, and on mobile Bartons there are many more multiplier remaps. For example 7X becomes 15x, 7.5x -> 22.5x, 8x -> 16x, 8.5x -> 16.5x, and more.
So even though I can't literally choose "16X" I just set 8X and I get 16X.
For motherboards that don't have adjustable multipliers. You can still mod the L3 bridges or make socket mods and force the multipliers.
Now for your motherboard with which you cannot set the multiplier. In theory default multipliers should still work. Unfortunately some boards don't POST. Some POST with oddball multipliers like the KT7 and it's 20x. Some POST with the default multiplier but at 100 Mhz FSB (common problem). And I think there are other possibilities.
Generally, if you CAN get one unlocked, high multiplier CPU to POST then you get others to work. Sometimes wiremods work better than relying on the default multiplier. If you run into the issue of being stuck at 100 Mhz FSB then you are going to want a wiremod which the only workaround or the that issue.)
After saying all that, I don't know if a 16.5X processor will POST on your motherboard. It might. You will have to try it. From what I have read people that were successful with Tbred B's on legacy mobos were also successful with Mobile XP's.
As for "Auto Detect FSB", AFAIK, that is the motherboard detecting the condition of the L12 bridges via the appropriate pins on the CPU ands setting FSB speed accordingly. (I forget the name of those pins). Multipliers are not affected Auto Detect FSB (again, AFAIK).
@endyen
i am planning to upgrade my cpu not because of speed (it's not really bad slightly overclocked at 2.25 Ghz). i'm doing this primarily for the sake of getting 512k cache. i just dont feel like messing with l2 bridges on my thorton which actually has it (this is just not really my thing). i use this pc mainly for transcoding dvds and watching high-res mpeg4 videos and for that as i understand cache size means a lot.
@phsstpok
wow.. thanks a lot for all the invaluable info you posted here. i really appreciate that.
and thanks everyone else for your answers.
i'll be buying a new cpu sometime very soon and i hope i'll be able to post the results of the upgrade in this thread too.
and. everyone who finds more information on these newly discovered 4C Bartons is still most welcome to write about it here. i'm sure there's more things about them that we would all want to know.
