Overclockers Australia - KingMax PC150 256MB SDRAM

KingMax PC150 256MB SDRAM
Review by: James "Agg" Rolfe

You might remember the quite comprehensive roundup of KingMax's SDRAM offerings I wrote last year. KingMax's RAM is distinctive at a glance, their unique TinyBGA technology giving the sticks a characteristic low-profile look with no visible pins on the individual RAM chips. For some general background on KingMax, their TinyBGA technology and their previous SDRAM products I recommend you check out the earlier 3-page review because I'll be making a few references to it in this review. Today I'll just concentrate on their new 256MB stick of PC150 SDRAM - this is rated by them to run at 150MHz at CAS3.

Given that I've already reviewed the 128MB PC150 product, you'd be forgiven for questioning the need for a separate review of the 256MB unit. The answer to this lies in the writing on the PCB's of both sticks:

128MB uses the v1.2 PCB

256MB uses "new" v1.0

KingMax's numbering scheme is a little confusing with the new product being labelled "v1.0" while their earlier products were marked "v1.1" and "v1.2". Again, the answer is there on the sticks if you look for it.

128MB background, 256MB foreground - click to enlarge

On the silver stickers you'll notice the -883 and -683 on the 128MB and 256MB respectively. This indicates 8MB or 16MB individual DRAMS and there's the answer. If you can only have 8 chips per side per stick, and you've already filled the 128MB stick with 16x 8MB DRAMs, then obviously you need to get higher density DRAMS in order to make a higher capacity stick. The 256MB stick uses 16x 16MB DRAMS and you can see at a glance that they are physically larger than the older 8MB ones. This is why the PCB is labelled v1.0 - it's the NEW, 16MB DRAM v1.0 PCB. If it was me I would have avoided confusion by labelling it 2.0, but I'm sure KingMax have their reasons. If you recall from the earlier review, the original product was not actually labelled v1.0, it was only with v1.1 and above that they started putting the version number on the silksreening on the PCB.

closeup of the 16MB DRAM

Compatability
All this waffling about version numbers is important, because in the earlier review I noted that the original (unlabelled) v1.0 and v1.1 sticks had some compatability problems with certain motherboard chipsets. KingMax graciously offered to swap these sticks, under their lifetime warranty, with newer v1.2 sticks for people experiencing this problem. However, they have apparently been swamped with requests from people to get an upgrade when in many cases they ALREADY had the v1.2 or the NEW v1.0 sticks. If your stick has v1.0 written on it then you have a new stick (128MB is single-sided, 256MB is double-sided) and therefore shouldn't have the incompatability problem of the early sticks so your problem is most likely elsewhere in your system. Of course if you do have a genuinely faulty stick then it will be covered under the lifetime warranty.

So, the official word from KingMax Australia is that, if you have the 883 v1.0 PC133 stick (possibly no version number written on it) and have a compatability problem with your motherboard, you can send it to them (at your expense both ways, so include a prepaid registered postpack) and they will swap it for a 883 v1.2 stick of the same capacity and speed. So if you don't have a compatability problem don't bother, there's no advantage to it.

But anyway, the days of KingMax incompatability seem to be well behind us now - in the month or so I've had this 256MB stick here I've used it in motherboards based on Intel i440BX, Intel i815E, VIA Apollo Pro 133A, VIA Apollo Pro 133 and VIA KT133 chipsets - all with no problems. I've been using v1.2 128MB PC133 and PC150 sticks in testbeds for a while now and never had a reason to suspect the KingMax as causing a problem.

So, all that aside - as this is a new stick, with a new PCB design and using new DRAMs, it of course has the potential for completely different performance to what we've seen from the earlier sticks. That's the real reason for this review..

Performance
As we've seen in earlier RAM reviews, there's not really any speed difference between two sticks of ram at the same speed and settings. I tried the 128MB stick, the 256MB stick and a 128MB stick of Corsair PC133 all at CAS2, 133MHz in my P3V4X system and the scores were virtually identical. So no surprises there. The real point of interest for overclockers is, of course, how well the sticks overclock.

Reviewing sticks of ram is a tricky thing these days. With manufacturers rating their sticks to 150MHz and beyond, making a system that can push the ram beyond those limits is an interesting exercise in itself. After experimenting with a few boards and CPU's here I realised I'd have to go back to the old faithful unlocked P2-400.

I first tried the RAM in JimX's MSI BXMaster - with the CPU at 3x I could happily run each of the three sticks (The 128MB KingMax, the 256MB KingMax and the 128MB Corsair) at CAS2 @ 155MHz, the board's maximum FSB. By "happily" I mean it would boot into Win98SE and run Sandra 2001's CPU, MultiMedia and RAM benchmarks, then shut down without showing any errors. Of course, no 3D programs would run because the AGP video card was freaking out at the high bus speed - it's a BX-based motherboard remember.

Next I moved to my Asus P3V4X. This was comparable - I could run all 3 sticks individually at 116MHz FSB, which using the FSB+PCI option for the RAM speed runs it at 154MHz according to Sandra 2001. This was again at CAS2. At 118MHz FSB, or 157MHz RAM speed, the machine would fail to POST, even at CAS3, with any stick. I've seen the Corsair do 161MHz @ CAS2 so I know that's not the limit. I tried changing the video card and removing all other devices etc, but no joy - seems to be the motherboard itself conking out.

Still, 155MHz @ CAS2 is not bad at all. I can't tell you exactly what speed you can expect to hit with this stick of RAM, but realistically I think you'd have to expect other components in your system to start failing to cope before the RAM lets you down. Remember we haven't even needed to drop back to CAS3 yet.

Conclusions
Well, my experiences with this new 256MB stick have done nothing to change my opinion of KingMax. They seem to be offering decent quality RAM that overclocks well and is reasonably priced - and they back it up with a lifetime warranty. What's not to like? Still recommended. Thanks to KingMax Australia for supplying the review unit.