Boy, I just lost about a day of my vacation trying to unlock my xp1600+ w/o success. Maybe I was just too cocky, but I've never had such a frustrating computer hardware problem that was supposed to take an hour to complete. I read thru Tom's Hardware guide, saw his how-to movie, and search a bunch of forums to see the alternative methods and pitfalls. Yesterday morning I started w/ superglue, defroster repair paint (initially), tape, multimeter,and a good magnifying loop. As the day withered away, I tried whiteout, a conductive pen, and various desperate on the fly methods to seperate the individual L1 traces and prevent grounding. I was in one of those endless " Lemme try just one angle on this" loops. I dunno but on this particular cpu the L1 laser pits were very close to the bottom row of contacts and difficult to isolate:
L1 schematic:
o o o o o - top row of contacts
_ _ _ _ _ - "the pits"
o o o o o - bottom contacts
Either as a result of contact between several of the bottom contacts its "pit" or because I scraped of some of the top green cpu layer exposing the underlying copper, I keep finding electrical shorts between 2 or 3 of the bottom contacts and the little gold testing spot ( which I believe is continous w/ the underlying copper layer. When I tried the cpu after setting up the L1 traces, the multiplier was stuck at 8.5 instead of the default 10.5. I read that this is a sign of shorting out. Fortunately when I remove all the conductive paint and thus isolate the top contacts from the bottom ones, the cpu still runs at 10.5X ( whew! I lucked out there.) .
This is so frustrating. This is a good cpu running fine @ 152 fsb and 1600MHz. I believe w/ a higher multiplier I could get more out of it. Although I "gave up" on unlocking it yesterday at about midnight 'cuz I couldn't think of another approach, I was thinking..... maybe if I coated all the L1 exposed contacts, including "the pits" and the ones I created by scraping, w/ a coat of superglue, or epoxy (or applied very good adhering tape!), then poke thru the coating w/ a pin or similar right over the L1 contacts, and finally trace between the contacts w/ something I haven't used before, like thin wire or some other conductive liguid ( the silver conductive pen and the repair paint are too granular and brittle and crumble apart easily, especially if the surface isn't perfectly flat). Anybody know about a conductive liguid that might flow better around irregularites and down a pin hole and be more flexible?
I certainly hope everybody else has better luck than me at this !
L1 schematic:
o o o o o - top row of contacts
_ _ _ _ _ - "the pits"
o o o o o - bottom contacts
Either as a result of contact between several of the bottom contacts its "pit" or because I scraped of some of the top green cpu layer exposing the underlying copper, I keep finding electrical shorts between 2 or 3 of the bottom contacts and the little gold testing spot ( which I believe is continous w/ the underlying copper layer. When I tried the cpu after setting up the L1 traces, the multiplier was stuck at 8.5 instead of the default 10.5. I read that this is a sign of shorting out. Fortunately when I remove all the conductive paint and thus isolate the top contacts from the bottom ones, the cpu still runs at 10.5X ( whew! I lucked out there.) .
This is so frustrating. This is a good cpu running fine @ 152 fsb and 1600MHz. I believe w/ a higher multiplier I could get more out of it. Although I "gave up" on unlocking it yesterday at about midnight 'cuz I couldn't think of another approach, I was thinking..... maybe if I coated all the L1 exposed contacts, including "the pits" and the ones I created by scraping, w/ a coat of superglue, or epoxy (or applied very good adhering tape!), then poke thru the coating w/ a pin or similar right over the L1 contacts, and finally trace between the contacts w/ something I haven't used before, like thin wire or some other conductive liguid ( the silver conductive pen and the repair paint are too granular and brittle and crumble apart easily, especially if the surface isn't perfectly flat). Anybody know about a conductive liguid that might flow better around irregularites and down a pin hole and be more flexible?
I certainly hope everybody else has better luck than me at this !