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Power Macintosh 7500 Capacitor Replacement Guide

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Logic board 820-0752-A with its surface-mount electrolytics circled: red 47 µF 16 V, cyan 10 µF 16 V, magenta 4.7 µF 25 V. Photo: MrFahrenheit; annotation: MacDat

The Power Macintosh 7500, 7600 and 8500 logic board 820-0752-A carries surface-mount aluminium electrolytic capacitors of three values: 47 µF 16 V, 10 µF 16 V and 4.7 µF 25 V. Console5 lists 34 positions on the front and rear of the board, and MacDat's annotated photograph of the front marks 22.[1][2] The photograph shows aluminium cans. Apple's Service Source treats the logic board as one part and gives no component values.[3]

820-0752 is the board that Apple's charts name as supporting cards on the DAV connector in Mode 2; boards marked 820-0564 need Apple's jumper-wire fix to do so.[4] No capacitor list has been published for the 820-0564 board or for the 7300 board, which owners identify as 820-0858-B.[5] Read the number printed on the board before using the table below.

Logic board capacitors

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Logic board 820-0752-A, from Console5
Side Position Value Voltage
Front C49 10 µF 16 V
C56 10 µF 16 V
C61 47 µF 16 V
C85 47 µF 16 V
C86 10 µF 16 V
C103 10 µF 16 V
C108 10 µF 16 V
C109 10 µF 16 V
C116 47 µF 16 V
C125 47 µF 16 V
C130 10 µF 16 V
C151 47 µF 16 V
C170 47 µF 16 V
C177 47 µF 16 V
C189 47 µF 16 V
C190 47 µF 16 V
C193 4.7 µF 25 V
C194 4.7 µF 25 V
C195 4.7 µF 25 V
C196 4.7 µF 25 V
C197 4.7 µF 25 V
C230 47 µF 16 V
C231 47 µF 16 V
Rear C362 10 µF 16 V
C369 47 µF 16 V
C372 47 µF 16 V
C373 47 µF 16 V
C383 47 µF 16 V
C392 47 µF 16 V
C396 47 µF 16 V
C432 47 µF 16 V
C435 47 µF 16 V
C440 47 µF 16 V
C452 47 µF 16 V

Console5 notes that C56 is a 47 µF 6.3 V part on some boards and considers that likely to be wrong, recommending 10 µF in its place.[1] Console5 lists eleven 47 µF parts on the front of the board; MacDat's photograph of the front marks ten, with the same seven 10 µF and five 4.7 µF parts, and shows nothing of the rear.[1][2] The 4.7 µF 25 V parts sit in a row of five, and the 10 µF parts are mostly near the I/O connectors.[2]

Owners report that the 8500 version of the board has all of the video chips fitted, the 7500 and 7600 versions about half and the 7300 none, so a position fitted on one model can be empty on another.[5] Count the parts on your board and replace only what is fitted.

Inspection

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Swing up the internal chassis or remove the board as described on Power Macintosh 7500 General Maintenance. Look for:

Capacitor Failure Symptoms describes what failing parts look like.

Replacement

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  1. Photograph both sides of the board and record the value, voltage and polarity of every part before removing anything.
  2. Remove each capacitor with hot air or two irons without lifting the pads, and clean away electrolyte with isopropyl alcohol.
  3. Fit parts of the same capacitance and at least the same voltage rating, observing polarity. On an aluminium electrolytic the marked side is negative; on a tantalum the stripe marks the positive end.
  4. Do not fit capacitors to empty pads. An owner who added two capacitors to empty positions while recapping a 7300 board, and later removed them, found the computer would power its fan and LED but gave no chime and no picture.[6]
  5. Check each new part for a short to ground before the first power-up.

Power supply

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The 7500 and 7600 use Apple's 614-0039 supply, made by Delta (DPS-150GB) and ASTEC, the same unit as the Power Macintosh 7200. No capacitor list for it has been published; owners' notes on its glued capacitors and on resistor R41 are on Power Macintosh 7200 Capacitor Replacement Guide.[7] The 7300's supply has a different logic board connector. The primary capacitors hold mains-derived voltage; discharge them and confirm with a meter before touching the board, and check the 115/230 V switch before the supply goes back in.

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References

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  1. ↑ 1.0 1.1 1.2 Console5 Tech Wiki, "Power Macintosh", section "7500 / 7600 / 8500: 820-0752-A" (secondary source; read 2 October 2026). Console5 sells the set as a tantalum kit.
  2. ↑ 2.0 2.1 2.2 MacDat, "Power Macintosh 7500 Capacitor Reference" (same data on the 7600 and 8500 pages): logic board, 47 µF 16 V × 10, 10 µF 16 V × 7, 4.7 µF 25 V × 5, all surface-mount electrolytic; photo from MrFahrenheit (secondary source).
  3. ↑ Apple Computer, Service Source: Power Macintosh 7300/7500/7600 & WS 7350 (1997), exploded view, PDF p. 170: logic boards 661-1154, 661-1219, 661-1266, 661-1783; power supply 661-0920. File:Pm7300.7500.7600.ws7350.pdf; see Power Macintosh 7300/ 7500/7600 & WS 7350 Service Source.
  4. ↑ Apple Computer, Service Source: Power Macintosh 7300/7500/7600 & WS 7350 (1997), PDF pp. 71–72: boards with 820-0752 silkscreened support DAV cards; 820-0564 boards need a jumper-wire fix near U18.
  5. ↑ 5.0 5.1 68k Macintosh Liberation Army forum, "7500 Power Supply Woes" (2021): 7300 logic board part number 820-0858-B, with a 24-pin power connector; trag: the 8500 board has all of the video chips fitted, the 7500 and 7600 boards about half and the 7300 none.
  6. ↑ 68k Macintosh Liberation Army forum, "Power Mac 7300 issues post tantalum" (2020): two extra capacitors fitted to unpopulated pads on the multi-model board during a recap; after their removal the machine still gave no chime or video. A 2025 reply reports the same symptom after a recap, with no fix posted.
  7. ↑ 68k Macintosh Liberation Army forum, "Need Resistor Value from PowerMac 7600 Power Supply Delta DPS-150GB" (2025–2026): 614-0039 supplies from a 7500 (ASTEC) and a 7600 (Delta); Console5 recap kit; glued capacitors; R41 845 kΩ.
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