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File: 39 KB, 677x580, Dx4.png [View same] [iqdb] [saucenao] [google]
6008478 No.6008478 [Reply] [Original]

Question about jumper configuration for DX4/100. Hi all. Putting together a DX4 build and I know that chip requires 3.3v. Got a compatible motherboard, but the JP40 which I need to short doesn't have pins. Rather it has a voltage regulator slot (JP26), but I can't find that part anywhere. I'm thinking the manufacturer eliminated the pins in a revision to guard against people from frying their chips.

So wondering if I could just short the pins the hard way by soldering some wire between the pins? Also, I assume the power supply will draw the 3.3v and I don't need a specific PSU with a 3.3v rail or something? Appreciate any help.

>> No.6008489

>>6008478
>Rather it has a voltage regulator slot
Pictures please.

>> No.6008502
File: 2.55 MB, 1139x1003, Jumper.png [View same] [iqdb] [saucenao] [google]
6008502

>>6008489
And that slot next to the circled part is the voltage regulator slot. Here's the manual. Page shows use of the regulator.

https://manualzz.com/doc/28425136/um4981-aio-rev-2.1

>> No.6008503

>>6008502
>Page shows
*Page 20

>> No.6008529
File: 17 KB, 400x286, InigoMontoya.jpg [View same] [iqdb] [saucenao] [google]
6008529

>>6008478
>voltage regulator slot
>that slot next to the circled part is the voltage regulator slot
zoom

>> No.6008545
File: 73 KB, 679x888, 20.png [View same] [iqdb] [saucenao] [google]
6008545

>>6008529
Okay, header. Thanks for the help.

>> No.6008605

OK OP, I think I got it now. You know your chip is using 3.3V? Then you need to bridge those pins on JP40 and use a PSU designed for a 3.3v CPU. The voltage regulator slot is only if you are using some special snowflake CPU that needs 3.45v, 3.6v, 3.9v, or 4.0v, and it just gets bridged all the way across if you are using a 5.0v CPU. It remains open and ignored for 3.3v if you are using a PSU with 3.3v connected to P2.

>> No.6008608

>>6008605
Er, pads, not pins. You could also install pins on those pads using some legs off of some capacitors or resistors, then put a jumper on them if you ever plan on changing CPU.

>> No.6008619

>>6008605
Yeah, going to use a 3.3v DX4/100. I do have an AT PSU with a min 3.3v rail that did come out of a dead DX4 machine. I'll probably solder in some pins and jumper them that way. Thanks for the help.

>> No.6008903

>>6008545
Sure thing. Always happy to help.

>>6008608
And might want to check those pads before doing anything with them. There might be a reason there aren't pins in them.