Identifying a Jasper

Unlike the Falcon transition, the move to Jasper isn't very clean cut. You can't rely on a lot number or manufacturing date to tell you whether or not you've got a Jasper, there are some hints and only one sure-fire way to determine if you're holding a box with a Jasper inside without actually opening the packaging.

The hints are pretty basic: the Xbox 360 Arcade bundles appear to be the best chance at getting a Jasper right now, although there have been reports of some Xbox 360 Pro systems featuring Jasper. As of now there haven't been any confirmed Elites that have the Jasper boards in them. Remember that Jasper is not only a potential fix for the RRoD, but is also a cost reduction for Microsoft - the GPU die is smaller and the power supply is less powerful, which means lower overall costs - something that makes the most sense in the most price constrained of the three Xbox 360s available today: the $199 Arcade.

Xbox 360 Arcade Things to Look For Likelihood that You've Got a Jasper
Lot # 0842X or newer Maybe
Xbox 360 Arcade Sticker Markings XGX-00019 Probably a Guarantee
Xbox 360 Arcade Sticker Markings Value Bundle 2008 E Probably a Guarantee
Current Rating on 12V Rail 12.1A Guaranteed


The first thing you'll want to do is look at the sticker on the outside of the box, this will have the lot number, team and some other potentially useful information. The lot numbers you're looking for are 0842X or newer, although unlike Falcon-hunting, the lot number won't guarantee you a Jasper. The lot number refers to the year and week that the console was built, 08 being the year, 42 being the 42nd week of the year. The X is there for, well, good luck I guess. The team isn't as important as it was in the Falcon days either, Xbox 360 Arcade bundles marked lot 0842X from team CSON and FDOU have been both Jasper or Falcons.

If you can't rely on the lot number and manufacturing team, then what can you? The sticker on the side of the box holds the first clues, while you can find the lot number here that's just a quick way of determining the likelihood of you having found a Jasper (e.g. if your lot number is really old, like 0830 then it's not a Jasper). There are two lines that right now appear to be good indications that you may have found a Jasper, I've highlighted them in the picture below:

If you see this XGX-00019 line below the top barcode, chances are that you've got a Jasper. And if you see this Xbox 360 Arcade System Value Bundle 2008 E line (exactly like that, note that this only applies to Arcade units) then you most likely have a Jasper as well. If you want full confirmation though you'll need to look at the current rating on the 12V rail which, believe it or not, you can do without ever opening the box.

Microsoft cut out a little window in the Xbox 360 packaging to allow the barcode/serial number to be scanned. Looking through this window the information you want is most likely obstructed by the cardboard cutout and it's to the left of the opening. The least destructive way to get access to this information is to push down on the Xbox 360 itself through the window on the right side, which will hopefully reveal the information you're looking for. A quicker, easier and potentially get-you-kicked-out-of-the-store way is to push the cardboard itself to the left a bit, possibly even tearing it slightly, to reveal the text you're interested in. The line you're looking for is this:

12.1A on the 12V rail nets you a Jasper

The important text is the current rating on the 12V line, which is immediately to the left of the current rating on the 5V rail. The three options here are 16,5A, 14,2A and 12,1A. All that really matters is the last digit, if you see a 5 then you've got a Zephyr, if you see a 2 you've got a Falcon (most likely) or if you see a 1 you've got a Jasper (take it and run).

12V Current Rating Xbox 360 Revision
16,5A Zephyr
14,2A Falcon
12,1A Jasper


Now some Jaspers have been mislabeled as 14,2A, but no Zephyr or Falcon has been mislabeled as 12,1A. The explanation is simple, this rating indicates what sort of power supply you'll need to use with the machine. Zephyr and Falcon boxes can't run with only 12.1A on the 12V rail, you'd end up with a box that either crashed a lot, rebooted or had other undesirable behavior (assuming it would even start, assuming you could even find a power supply that you could plug into it). There's only one Xbox 360 power supply that can deliver a max of 12.1A on the 12V rail, that is the 150W power supply that is keyed to only work on Jaspers. Find a machine with 12,1A written on the back of it and you've got yourself a Jasper.

Sneaky Microsoft: Still Shipping Zephyrs

In my Jasper hunting I came across a strange beast, I found an Xbox 360 Pro with lot number 0843X. I figured it was new enough that it could be a Jasper, but looking at the 12V current rating I found that it was a 16.5A unit. I thought perhaps it was mislabeled and I'd heard about some newer systems having a 16.5A 12V rating, so I thought I'd buy it and take a closer look.

Once I got it home I confirmed: the machine was a Zephyr, that's the original Xbox 360 hardware with HDMI support, meaning a 90nm CPU, 90nm GPU and 90nm eDRAM - the very configuration most likely to Red Ring. I'm guessing it's a reworked Xbox 360 that never made it out of the factory in the first place due to an instant failure; something Microsoft fixed and sent out at a much later date.

Even if you don't care about getting a Jasper, it may be worth looking into what it is you are getting to make sure that you're not stuck with a box that's more likely to fail.

Index Confirming Your Jasper


View All Comments

  • strikeback03 - Wednesday, December 10, 2008 - link

    In the US we would say the number 12.1 as "Twelve point one". In places where comma and period usage are switched, how would 12,1 be spoken? Reply
  • Spoelie - Thursday, December 11, 2008 - link

    "twaalf komma een"
    just as you say "point", we say "comma"
  • strikeback03 - Thursday, December 11, 2008 - link

    Interesting, thanks! Reply
  • Spivonious - Wednesday, December 10, 2008 - link

    Not European, but I believe it's "12 mark 1" or still "12 point 1" (i.e. in German it's 12 punkt 1, which translates to 12 point 1". Reply
  • geogaddi - Wednesday, December 10, 2008 - link

    No - Krauts write "12,1" and say "zwoelf komma eins".

    Now comes the time to dance. Dieter, touch my monkey...
  • dasyentist - Wednesday, December 10, 2008 - link

    ''The Xbox 360 had a bit more graphics power than a Radeon X800 XT''

    Maybe i'm wrong but from the spec ive read it look more like the core of a x1800/x1900...
  • JarredWalton - Wednesday, December 10, 2008 - link

    The Xenos GPU is somewhere in between X800 and X1800. It has more in the way of X1800 hardware, but performance is a lot more like X800 I believe. Neither the Xbox 360 nor the PS3 launched with graphics performance that could match - let alone surpass - that of the then-current top PC GPUs (i.e. X1800 and 7800 GTX). But, there is something to be said for having a static hardware to target when making games. Reply
  • george12 - Tuesday, May 5, 2009 - link">">
  • bill3 - Thursday, December 11, 2008 - link

    I was going to comment on this glaring innacuracy in the article as well! See I'm not the only one who spotted it.

    Xenos doesnt match well to any specific ATI PC hardware of the time, being custom, but I feel fully confident in declaring it a good deal more powerful, in fact a generation ahead, of X800XT!

    The simplest way to deduce this is to compare to PS3. The RSX in PS3 is simply an 500 mhz 7800GTX with a 128 bit memory bus and a few other minor modifications (such as larger texture caches so it can handle the larger latency from PS3's XDR memory pool). The 128bit bus is not a huge handicap for many reasons. (low 720P rendering resolution, the fact RSX can texture from XDR as well as GDDR for more BW, etc etc).

    Now 360 outputs roughly the same level of graphics as PS3 overall (while a few PS3 exclusives seem to look slightly better, OTOH most multiplatform games look/run better on the 360). So it's a necessity to assume Xenos is at least roughly as powerful as 7800GTX. Does X800XT fit that bill? No. In fact the 7800GTX and it's same base specced but higher clocked brother the 7900GTX, traded blows against the ATI X1800 and X1900 cards of the time. So it's much more reasonable to place the Xenos with the X1800/1900 class ATI cards. I believe tape out times would also support that. I believe Xenos taped out in the same time frame (late 04) as G70/R520.

    You can also derive that Xenox>X800XT from more complex maneuvers such as execution resources (and probably die size as well, though I dont have that info). Xenos has 48 shader ALU's. Comparable to the 7800GTX which has 24 pipes, with 2 alu's each, for 48 (though it would also contain 6-8 vertex shader ALU's). And X800XT would have 16 pipes X2 ALU's =32 (plus 8? vertex shader ALU's). Now there are all sorts of caveats in comparing ALU's across different parts (if anything Xenos is probably a lot more efficient in utilizing it's more plentiful ALU's over X800XT, due to it's unified shading abilities, and it's ALUs can crunch an extra component as well I believe making the difference even greater), but nonetheless it probably tells us something.

    Heck, Xenos even has more raw shader resources than X1800XT. X1800 had only 32 shader ALU's as well, albeit higher clocks. Xenos is probably somewhere between X1800 and X1900 if you ask me, right in that class.

    Another evidence of this is the games, I'm not familiar with Gears of War PC benchmarks, but I bet even at 720P a X800XT would be crushed by the game, let alone Gears 2 (even allowing for the greater optimization in consoles doesnt go far enough to negate this point imo). I also dont believe games that look as great as Rage, Resident Evil 5, etc would run on an X800XT.
  • Anand Lal Shimpi - Thursday, December 11, 2008 - link

    The Xenos GPU should have fallen in between the R420 and R520 in terms of performance, remember that Xenos was ATI's first unified shader architecture GPU so direct comparisons between it and the non-unified ATI architectures of the time aren't exactly the easiest to make.

    We originally proposed that the Xenos GPU would perform similar to a 24-pipe R420, but you're correct in that it should be closer to the X1800 in performance. I will update the article to reflect that its performance falls in between both R420/520 but is closer to the 520.

    Remember that one major advantage Xenos has is its 10MB eDRAM, which definitely helps in the effective bandwidth department - making rendering with AA at 720p much more possible than other high end PC architectures available at the time.

    Even if you make the 7800 GTX comparison, we're still around 4x the speed of that with high end PC graphics today. G80 was 2x G70, and GT200 is 2x G80. By the end of next year we'll hopefully have something that is 2x GT200.


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